Just block those addresses and if they are real human then they will change address and use your faucet.
If someone blocks my address and if I have any referrals I will assume the owner is liar who bans users after they get referrals so he won't need to pay them bonuses. (that has happened with few faucets)
And in that case I wouldn't waste my time to try get new referrals with my new address because it probably would happen again.