Hm... to claim the coins they saved, you have to receive and send a small transaction from the compromised wallet to verify ownership. But how do they make sure

Hm... to claim the coins they saved, you have to receive and send a small transaction from the compromised wallet to verify ownership. But how do they make sure that it's not claimed by the hackers who may have the seed of these wallets? The only thing they say is that they don't send it if there is multiply claims (probably one from hacker and one from real owner).