Coinroyale doesn't seem rigged to me. I played a bit and the win/lose ratio seems to be very close to 50%. I think I had about 55%-60% of my hands in BJ were wins.
I don't think coinroyale is rigged. You can verify your bets with the probably fair system.
I guess people lost a lot in a losing streak when they try to use the martingale betting method and try to find an excuse for the loss.