I haven't been on Avid in quite a while, so I'm just running though some troubleshooting ideas (not intended as part of a realistic workflow).
I'm suggesting to manually relink just to see what happens. When I'm troubleshooting I tend to create a test project with clips for testing.
It's not at all unusual for me to use FCP to first separate my footage into clips, capture those, and then import them into CatDV. My process is slightly different because I'm coming off of HDCam tape. Which formats are giving you trouble?
here's a brief explanation of attaching media. I've had to do it when I've recklessly moved footage around without regard to CatDV.
Non-linear: all the time and nothing but.