I think many of us here can empathize with the loss of a bike.
I'd feel some empathy if someone came to me indicating a bike I had was once theirs. But without a police report clearly showing the serial number, I wouldn't believe it, regardless what ID'ing info they offered. I park publicly, anyone could get that info.
If they were able to provide a police report with valid serial number, I'd be happy to work with them on tracing back where I got the bike. But I would make sure they understand there's a possibility nobody would get the bike afterwards depending on a few variables, not limited to where/when it was taken.
This happened to one of my friends a few years back. Had some audio equipment stolen out of his car. Had some very distinctive markings on everything (custom artwork) and even pictures of ownership. Local cops took it into evidence, it never came back out again. He followed up two years later only to learn it'd been released for police auction. Somehow that's normal?