To me it sounds like it's probably just a reference to the same VM.
If you moved the VM and then double-clicked it to run it from it's new location, it would create a new VM Library entry.
If you right-click > Show in Finder fromthe Library window, the greyed out one will likely not allow that to be clicked because it can't find the file (which is why it's greyed out in the first place).
You can safely delete it from the VM Library window.
The idea of a 'merge' is not possible, you just have to delete the erroneous entry, after first making sure it's actually erroneous.
-
Michael Roy - Product Marketing Engineer: VCF