FCP has no reason to look for the Unity, unless I’m missing something. Perhaps the Avid client software “Connection Manager”(v5.1 I believe) has something to do with this.
Another thought, in previous versions of Media Composer(2.7-3.0) we had problems with MC closing before the temporary bin lock files were deleted. This would cause those bins to be locked if you tried to open them in a different suite. You would have to go back to the first suite and relaunch Media Composer, close the bins then exit the app. to release the bin lock. Also, when we had FCP projects on the Unity I discovered that if two editors opened the same FCP project from the Unity both could edit as if they both had read write access to the same files simultaneously until the editor who open the project 2nd tried to render or save any changes at which point he would get an error message.