I think I figured it out. It appears that you are using the root directory of a drive for Media Cache, which is not supported by AE. It's possible to get into this state because PR and AE share the same cache directory. And if you migrated your AE preferences when updating to 14.2, AE will use the root directory settings from the older AE preferences. That is the actual problem, which results in the failure to use the (.mogrts) in PR.
We'll look into changing that behavior. In the mean time, you can try to workaround it by setting the AE preference for Conformed Media Cache, to use the default location, or a non-root directory.