Do you mean the screw thread is stripped ?
Or do you mean the head is stripped ?
Two options for the head strip. There are one time stripped screw kits you can buy where you drill into the screw head and insert the reverse screw supplied in the kit into the head of the stripped head screw. Then because the insert is reverse threaded, as you’re tightening it up it’s unscrewing the original stripped screw. I’m not sure if these kits go down to the size you need for the platter screws. Also, drilling makes thousands of particles of metal which you DONT want getting into your deck -so vacuum the localised work area regularly while drilling etc.
The other option is also one-time. Get an old screwdriver and super-glue/crazy-glue the head of the screwdriver to the damaged screw - once the glue has set you can Unscrew it