At sometime the SS screws will loosen/fall out. Buy 3M bondo and use a basting syringe to put a few drops in the damaged hole and a few on the screw. Then tighten "slightly" and the bondo will set up filling the damaged threads. You can also use Gelcoat
Before you fill it, I would check to see if there is moisture damage / rot, if your transom is a wood core. The moisture will need to be dried out or removed.
