It's a long shot but worth a shot. Your file manager probaly isn't up to this job so go to the Play Store and download Root File Manager - look for the bright yellow logo. It's free and safe to use and you don't need to root the device to use it.
Install it and whichever folder it shows, tap the little house to get back to basics. Search through the folders to find a sub-folder named Lost & Found or one named LOST.dir. They're likely to be in the System folder
It's the Android equivalent of Windows Recycle Bin so with luck, you might find them there.With