So, just posting for everyone's reference.  I had a client that could see an XDCAM XAVC file properly.  Weird part is that you could doubleclick on the file and it would load in the source monitor, but nothing else would work, couldn't link it or edit to a timeline.  Eventually it would go offline in the source monitor.  

After many reinstalls and AMA package verifications, we discovered that there was a permissions issue on Shared folder of the OS.  This made it so that the media composer could not write the AMA index file (msm) that tracks AMA media to that directory properly.  Once I set permissions for the current user (also the installing user) Everything started working properly.

The way this showed it may be a solution, is that we set the MacHD with the ability to create an Avid MediaFiles folder, then linked.  That worked fine.  But apparetnly when doing the same thing on another drive, it just couldn't write to it due to permissions.

Mac os 10.11.6, Avid 8.6.4.