Recover files on external drive

So, I bought a WD My Passport 4TB external drive recently. I used cut & paste to move approx. 100 GB of photo/video folders from an external SSD drive to the WD My Passport external drive. Long after the task was complete, I clicked on the "Safely remove hardware" option, and- in my haste, seeing in the corner of my eye the message "It's now safe to remove your..." I unplugged the WD (destination) drive, only to see at that moment, that the message actually was "Do not unplug your drive...". Basically I unplugged it early. Since then, the destination drive does not show the moved files- and the source drive, doesn't as well. Trash bins don't have the files either. My only hope... is the fact that the destination drive's capacity/empty space, reflects what it 'should be' if the files were successfully moved. So, it's clear the are in fact on the target drive, but... just not being indexed/shown.