I had a GP file that had a ton of stuff on it, bass, guitar, drums. And I imported it into EoF to make the guitar a dlc, however, I just noticed the original GP file is gone. Did it get moved or renamed somewhere? Is there any chance of recovering it?

It is not possible for EOF to have deleted, moved or renamed it.  If you happened to have enabled the "Import dialogs recall last path" import preference (File>Preferences>Import/Export), invoking Guitar Pro import again will have EOF default to that location and if the file still appears to be there, you can look at the folder path reflected in the file open dialog.  Otherwise you'd need to look in your file system (ie. perform a search for *.gp* in File Explorer).