For me "save scumming" means making backup copies of your save game, so that you can continue in case your PC dies. There is no way to detect this (except maybe on the ADOM operating system, but that's not available yet).
You probably think of "using a single save game to create multiple highscore entries". But since you can modify your local highscore file too, adding unique PC IDs would not help.
Our hope is that
a) players don't cheat
b) possible cheaters are reported (Thomas thinks it's realistic that the community can detect entries that look suspicious)
Since all highscore entries are bound to a specific user account, we can ban the cheaters' account and delete his entries.
“It's a cruel and random world, but the ChAoS is all so beautiful.” ― Hiromu Arakawa