My understanding is that the way the inner ear works it’s a coiled tube with thousands of tiny hollow towers in it with doors on the tops and strings on them like a harp. The strings occasionally snap. When they do the door stick open. You hear a single very pure tone for a few seconds and it gradually fades out. And that particular tone will never be heard again. Tinnitus is when you don’t stop hearing the tone.
The ear canal and the mouth ARE connected but they’re connected to the middle ear. The inner ear remains sealed away behind the ear drum.
Nicotine IS psychoactive, so it could affect the brain somehow, but the same thing would happen to smokers and I’ve NEVER personally heard of this being associated with smoking of any kind at all ever.
The site does have references but they're mostly nearly 10 years old. That’s the thing about a site this old. Just about every ailment on earth has been accused. “Vaping is causing my [X]” has been done for just about everything. Possibly including pregnancy, though I haven’t heard of that one either.
Theres astounding amounts of BS created by cigarette companies (yes they still hate vaping. They have since the beginning and they’ve never stopped even though they claim it because they’re STILL PRODUCING anti vaping stuff. They feel they have the right to hold a monopoly and have said so. Here.) which is handed to anti-smoking advocates (yes, this means the anti-smoking advocates are effectively working FOR the cigarette companies) and this may possibly be just more of that in action. I suspect that the tinnitus is associated with vaping approaches zero.
I’m not sure if the OP is a BSee or a BSer, but BS is involved.