It is very weird to see a question which obviously doesn't belong here is still existing. Furthermore has a bounty on it (I know it's user's discretion) and has an answer by someone. Now even though the answer has negative votes , it is eligible to be accepted? Seems really weird logic on both sides... Is there no possible control technique?
Question acceptance is purely at the question asker's discretion. They may accept any answer for any reason, or no answer if that's what they want.
The only limitation on whether a question can have a bounty made is if it is closed. You can also award bounties to answers with net negative scores.
If you think a question doesn't belong, then you should vote/flag to close it. Unfortunately placing bounties on questions prevents them from being closed. If the question is particularly egregious you can write a custom flag to ask a mod to cancel the bounty so that it can be closed. If you're looking at the same question I am I don't think it warrants the bounty being cancelled, but I will be voting to close it once the bounty is over. (As I did previously. I don't know why people want garbage like it to stay here.)