Been lurking for some time now but am compelled to post now that I have switched from pen's and vv/vw's paired with protanks and the such to mechanical mods and building. There is a ot going on in that title and I know most of you would suggest having three seperate threads but the are all realted to a certain extent. So, let's start with what caused the issue in the first place:
Possible fake MNKE 26650's:
I originally had the Chi You Megen by Tebeco clone as my personal vape but recently bought myself a copper Mutant clone also by Tobeco. Naturally my girlfriend inherited the Chi You so I bought us 2 more MNKE 26650's from ebay (first mistake many would say). We get the batteries and everything is going pretty well for a bit until this morning when my girlfriend wakes me up before leaving for work and tells me her mod isn't firing. I take it apart half asleep and make sure everything is secure, put it back together and, low and behold, it's not firing and has a vicious battery rattle. I take a hard look at the battery and see that it is clean, no indents on the top or bottom and look pristine. Now I had never had this issue before with the Chi You Megen so I look at some of the other batteries and start to piece together the issue. (for reference, in all picture the batteries will remain in the corresponding positions)

As you can see, the one on the left is taller, has a darker color and the infamous spacing in the I MR. Those fit nice and snug in the mod while the other one, which I believe to be authentic, does not. Weird thing is that it's the one I got from ebay and the buyer was almost sure they were not authentic. However, they have a very clean seem as opposed to a sloppy seem that is on the other (will provide picture if necessary, I am just limited to 5 photos per post), proper color, correct font and spacing and the bottom doesn't protrude a bit, it's completely flat and the tops have a very clean, well spaced white ring.

So, do you think either of these are authentic? Is there a meter that can determine if these truly are the real deal so that I can be confident in my .26 ohm builds? I read a lot about battery performance and safety, use my ohm meter constantly and never go under .22 ohm. While I have not, besides the way the shorter one fits in the Chi You Megen, had any issue with either battery in terms of performance or them getting hot, how can I find out if these ones are at the very least the same quality as the originals if they are both in fact fakes?
Now we tie this into:
Chi You Megen Clone and the Vulcan RDA Clone:
The issue with the no fire from the mod and the extremely loose battery needed a fix. The fix that I have going on currently with this setup is unscrewing the contact pin located in the 510 connection of the Vulcan to compensate for the shorter battery. Is that okay to do or does it compromise safety at all? It does have a Philips head slot so I though maybe it was there specifically for this purpose.

In order for this to work, however, I do need to unscrew the insulator located in the top cap of the mod a bit as well.

Now does that cause any issue as well? Neither the insulator or the contact pin in the Vulcan are unscrewed to the point that they are loose and unstable, they are just both unscrewed a bit.
I am sorry for this Illiad of a post, but I just want to make sure I am taking all precautions necessary and that I am doing things right. I know many here will jump at me for sub-ohming, but from what I have researched and read, there is a proper and safe way to do it and my builds have no pushed my batteries beyond their limits (if the batteries do in fact have the properties they should have). I send my girlfriend out with this build everyday and so I am just trying to look out for her as well by being as thoroughly informed about everything as possible.
I thank everyone who responds in advance and hope everyone is vaping safe!
Possible fake MNKE 26650's:
I originally had the Chi You Megen by Tebeco clone as my personal vape but recently bought myself a copper Mutant clone also by Tobeco. Naturally my girlfriend inherited the Chi You so I bought us 2 more MNKE 26650's from ebay (first mistake many would say). We get the batteries and everything is going pretty well for a bit until this morning when my girlfriend wakes me up before leaving for work and tells me her mod isn't firing. I take it apart half asleep and make sure everything is secure, put it back together and, low and behold, it's not firing and has a vicious battery rattle. I take a hard look at the battery and see that it is clean, no indents on the top or bottom and look pristine. Now I had never had this issue before with the Chi You Megen so I look at some of the other batteries and start to piece together the issue. (for reference, in all picture the batteries will remain in the corresponding positions)

As you can see, the one on the left is taller, has a darker color and the infamous spacing in the I MR. Those fit nice and snug in the mod while the other one, which I believe to be authentic, does not. Weird thing is that it's the one I got from ebay and the buyer was almost sure they were not authentic. However, they have a very clean seem as opposed to a sloppy seem that is on the other (will provide picture if necessary, I am just limited to 5 photos per post), proper color, correct font and spacing and the bottom doesn't protrude a bit, it's completely flat and the tops have a very clean, well spaced white ring.

So, do you think either of these are authentic? Is there a meter that can determine if these truly are the real deal so that I can be confident in my .26 ohm builds? I read a lot about battery performance and safety, use my ohm meter constantly and never go under .22 ohm. While I have not, besides the way the shorter one fits in the Chi You Megen, had any issue with either battery in terms of performance or them getting hot, how can I find out if these ones are at the very least the same quality as the originals if they are both in fact fakes?
Now we tie this into:
Chi You Megen Clone and the Vulcan RDA Clone:
The issue with the no fire from the mod and the extremely loose battery needed a fix. The fix that I have going on currently with this setup is unscrewing the contact pin located in the 510 connection of the Vulcan to compensate for the shorter battery. Is that okay to do or does it compromise safety at all? It does have a Philips head slot so I though maybe it was there specifically for this purpose.

In order for this to work, however, I do need to unscrew the insulator located in the top cap of the mod a bit as well.

Now does that cause any issue as well? Neither the insulator or the contact pin in the Vulcan are unscrewed to the point that they are loose and unstable, they are just both unscrewed a bit.
I am sorry for this Illiad of a post, but I just want to make sure I am taking all precautions necessary and that I am doing things right. I know many here will jump at me for sub-ohming, but from what I have researched and read, there is a proper and safe way to do it and my builds have no pushed my batteries beyond their limits (if the batteries do in fact have the properties they should have). I send my girlfriend out with this build everyday and so I am just trying to look out for her as well by being as thoroughly informed about everything as possible.
I thank everyone who responds in advance and hope everyone is vaping safe!