I would like to propose an idea, you don't have to take it seriously, but it's an idea.
What if Old Man Marley wasn't there to rescue Kevin, and the Wet Bandits chose to simply abduct the trapper, the new plan having been to ransom Kevin for a good payout. Marv, however, makes the suggestion that they take the money, keep Kevin, and fake their deaths. The duo use a pipe bomb, their trusty old van, and a few deceased homeless people to make their great escape.
That was seven years ago, Kevin spent his first three years as an unwilling guest of the duo, and then Stockholm Syndrome kicked in. At the age of fifteen, Kevin loses his second family after a job goes wrong in Gotham when Harry and Marv attempt to burglarize the seemly abandoned Zsasz Manor only to run into Victor Zsasz himself.
It's a bit darker, considerably darker, but with his birth family being alive and yet he is presumed dead. The Wet Bandits had a better and longer run of things, it all ended when they ran into Victor Zsasz. Now Kevin has to start from scratch, maybe there's a Cafe hiring or something?
Oh wow I love this idea so much actually!!
There's a fanfic that was actually recommended to me by a different anon that involved the idea of Kevin being taken by Harry and Marv and having Stokholm syndrome!! It was super cool to read, but throwing Batman into that, is so cool to think about!!
This is actually the fic I was given from back then!!
https://www.fanfiction.net/s/12813426/1/Home-is-Where-the-Heart-is
But to continue on, I imagine Kevin's got some amount of funds to help himself out for a bit before he needs to 100% worry about being on the streets. Since this is 7 years after the first home alone, this means that Kevin is 16 (he was 9 at that time), so it's not suspicious for someone his age to get a job.
He'd definitely be on the young side if he ends up doing goon work, but Kevin would more than likely not stick to a villain for too long a time so he can avoid being recognized.
Kevin's a caring kid, and probably was made to believe his family has moved on and so to him Harry and Marv are much more important. So instead of trying to reconnect with his actual family, he's going for revenge against Victor Zsasz. He's just trying to get all his ducks in a row first, and avoid being found out by his bosses/the batfam.
