The bacteria in ACV converts alcohol into acetic acid (vinegar), not the other way around. Alcohol can cause liver issues, but not vinegar.
The reason people use ACV (or any vinegar) is to lower the pH of a new batch of ff. It doesn't have to have "the mother" or any thing like that, even white vinegar will work.
The reason that people use buttermilk is to both lower the pH and add a few more beneficial lactic acid bacteria.
But neither is required. But lowering the pH will speed up, slightly, the fermentation process of a new batch. And increase your chances of it turning out right..,a handy tool if you've never fermented before.
You could also add a few cabbage leaves, if you have some around, to add some lactic acid bacteria. It will help speed it up...but again, not necessary.
This assumes you are using non chlorinated water. If you have chlorinated water, call your municipal water supply to find out if its chlorine or chloramine. The former can be off gassed, as ChickenCanoe said, the latter needs other methods. Sounds like some folks do okay with it. There's a chance it might work just fine but it's also increasing your chances of it going bad. Or you can try adding starters like buttermilk or salt less kraut juice or several cabbage leaves...but I haven't experience with chlorinated water.
