information like deposits and withdraws are all stored in a mysql database
Though, I remember him using Blockchain API. If that is the case, the info is there as well?
No, you cannot do this.
Think about a gambling site. Every deposits money and bet. Then the MYSQL db gets corrupted. Now, the owner doesnt know how much people have bet since the DB is lost. All he know is how much BTC he received. Some users can lie and say they had their full balance and didnt bet and get a full refund.
This is the position that Carlos is in.