Saves are stored locally. Check in the Saved Data in System Storage section of the Settings menu, to see if there are saves there not shown in-game. If that is the case, click in Saved Data in System Storage, click Copy to USB Storage Device, select one or two relevant saves and Copy. From there you can zip the files on a computer, and email them (or a Dropbox or Google drive link, etc) to supportdos2@larian.com.
If there are no later saves there, maybe PSN synced in the wrong direction the last play session? That has not been reported before on PS4, though (has happened at least a couple times with Steam on PC).