Not sure how to help; except to say that (in my experience) everything that was put together comes apart. (unless it's welded, in which case it takes a grinder...
) Whether or not it can ever be put back together after being taken apart, is sometimes a different matter... I'm seriously considering buying one of these critters; though; so, I'd be VERY interested in hearing your outcome. If I were tinkering with one, I think I'd take a needle or something similar and a magnifying glass, to search for any hard to find seams. I'd especially search around the area behind the button. (Where the connector would press into a battery cover, if it were attached to a battery, instead of to a wire.) I've only seen the pictures; but, I've been thinking about building one using a pre-wired 510 connector and the old USB cord from a dead mouse. If I were building something like this, I'd tie a knot in the USB cord after passing it through a hole in something to hook the 510 connector into. Maybe who ever designed these had a similar thought. Actually, I got the idea from having an 1100 battery start trying to work it's way loose from the battery tube. Hope this helps.
Please keep us updated. If you decide not to mess w/it and to pitch it instead, pm me. I've enjoyed taking things apart ever since I was a little kid. LOL, SOMETIMES, I even manage to get them back together in some semblance of a working order...