Does blacklisting users kick them out of the already made GAs?

It won't remove him

You can't kick anyone using blacklist, but you can reroll that guy (if he wins) if there are valid reasons for this.
--__-- That suspicious person is you ?

Best case scenario is to recreate the GA and to make the replacement in such a way that the sus account cant access it. Which means either sharing it to a few or in a restricted capacity or a ratio restriction like Sgtools. In any case, since u have them Blacklisted they wont be able to reenter.

I highly doubt u will be able to reroll the current one, since it wasnt leaked. BL-ing the user isnt a valid reason afaik. So if they win, u would be forced to unblock them and gift 🙈

"The giveaway didn't leak, it was more like a loophole in rules"
Well, they'd either have to be in your whitelist or in the group giveaway to be able to enter.
If they have violated a group rule, then you should be able to re-roll, but if they've technically done nothing wrong... tough luck.

Also, sorry, I'll remove myself.