I think it can depend on the site or casino where you want to invest your bitcoin, need to be very much careful as there may be some casino or gambling sites that can easily scam you, if you want still invest your money there then you must first get good information first and then you can try with only your affordable to lose money.
Some trusted sites even turn into the dark side in the past. There are some famous sites in the past that actually stole alot of bitcoin from their user investment. In the end when you trust your money in someone's hand then consider it not safe at all, afterall there is no guarantee to the safety of your money even in your own hand
I dont however Im just telling the truth, if you put your money in someone's possesion then he or she could do anything with it so even if you put it to the most trusted person on the earth there is no guarantee that your money is safe however we do know the fact that there is no scammer until it is proven otherwise
( IF you know what I mean )