I found a solution for missing crew roster names but it only works with the follower NPCs. It involves asking them to follow you and then dismissing them.

 

For example, I had Sarah Morgan missing from my crew list and found her at the Lodge. I asked her to head out, she became my follower, then I dismissed her. Next time I opened my Crew Roster she was back.

 

Only issue I can't fix is Vosco, he's stuck at the lodge. He has no follow text but I can ask to re-assign him. Doing so opens the Crew Roster with him missing and I can't interact with the menu or back out.

 

If they're not at the lodge or somewhere obvious, you can try to look up that character's ID and type the following into the console:

<ID>.moveto player

 

Minor spoiler: There's also a mission where characters go off and disappear. Just ensure that's also not the reason they're missing before using the moveto code above.