I think you would be well served to take this job.
In navigating larger workplaces, my tactic has been to 'not see' people. I don't make eye contact unless it's someone I'm talking to. My eyes are looking where I'm going, not acknowledging people (at least, people I don't get on with). I avoided charges of favoritism by not chatting a lot with any one person. ("Gotta go. I have work to do) To happen into a job like this *at a time like this* is fortunate, indeed. I know you say you're over him, but the tone of your postings sounds as if you are still very emotional over him and the situation. (Just look at all the exclamation marks when you write about him) He tried to throw you out, soaked you with a hose, basically told you that if YOU straightened up, you'd be welcome back but otherwise, NO - - - then you felt 'obligated' to send condolences to someone who had been very, very, very clear he wanted you out of his life. He really and truly wants nothing to do with you. It may be stupid to reject people who love him, but it is his right.
He may not be well-liked, - but - no one held a gun to his colleagues' heads and made them vote for him as shop steward. There IS some loyalty or respect there, so proceed with caution.
Your last comment, "He may relent after some thought" sounds like you are still very attached and wanting a relationship. Make sure you're doing this for the right reasons. I don't think he's coming back to you, and your last sentence is a puzzling one that hints that's your goal.