If the owner of the account is innocent and their account was compromised, it's on them to come out and say that. All signs currently point to the person being a malicious actor, so I'll proceed on that assumption.
Probably not. I did some pattern of life analysis on their email/other identifiers. It looks exactly like when I set up a burner online identity- just enough to get past platform registration, but they didn't care enough to make it look real.
For example, their email is only registered to GitHub and Twitter. They haven't even logged into their Google account for almost a year. There's also no history of it being in any data breaches (because they never use it).
It would be interesting to hear the whole arc of social engineering behind getting access to the repo. Although, as a maintainer of a large-ish OSS project myself, I know that under a lot of burden any help will be welcomed with open arms, and I've never really talked about private stuff with any of them.