I really don't have very much for you, unfortunately. Of my played characters Victor is the only connection - they would have been coworkers (different departments though) before Victor died. They probably wouldn't have been friends though, very different stages of life and different backgrounds.

You know who might make a good friend? Gideon Ollivander. Similar "single dad who had a kid pretty young" vibes, both MC dudes too committed to work. This doesn't help you since he's super inactive but just throwing it out there. xD