60 btc of his own money yes. He (most certainly) invested several hundred BTC to earn from others' deposits, and also took fees from this.
It might not always be true. All deposits have a risk. Its hard to know when do you get paid, as that completely depends on deposits coming in the future.
Once you deposit , then you have to wait for more people to deposit. Depositing a big amount in the start also might not help, as people investing after that, will not tend to invest due to the already high amount invested.
However, if a lot of activity happens during a time frame, then that might be a time he might have invested.
So if the game isn't salted at the start and later the operator feeds the Ponzi, I bet most players would like that. However that would be very high risk and just collecting the fat fees is low risk.
