I stopped believing in all of this betting signals to be honest with you, I've lost a good sum of money on things like this in the past, and that only proves one thing which is that there are actually no short cuts to winning and making good money from betting/gambling, it's either luck is on your side or you will end up losing your money.
Crash game like we all know is a luck based game, and except a person hacks the game algorithm, there is not possible way to predict the outcome of every round, so, I do not believe the claim of the admin of that WhatsApp group of channel to be true, except he or she is working with some really strong people from inside the casino, which is very rare to happen if you ask me.