All of the mining information and the accounts are on chain. You can see which accounts are mined from steemd of you look at the account details, there is a section. I don't know how to search it as I don't have access to the SQL databases, but it is possible. Most of the miners are quite open that they mined. There is nothing wrong with those who mined - but it wasn't a fair mine by design.

Which hack are you speaking of?