Handing out these refunds likely scarred investors away which ultimately lead to having a bank roll that is not capable of sustaining a little bit of bad luck.
By the looks of it this wasn't "a little bit of bad luck".
From what I'm hearing people who stayed invested for Mateo have lost around 85% of their investment. Losing 85% of your site's bankroll with a dynamic 0.5% max profit is more than just "a little bit of bad luck".
like I said they should roll back mateos bets. But a bankroll that has players betting the max a high percentage of the time will be adversely affected if one person has a little bit of good luck. I would say that not all of the 15% losses that investors sustained were from him (most probably were) but some percentage were from other legit players who had a lucky streak and stopped.