I am not surprised to hear something about financing a gambler. There are many things that are yet unknown to me in the gambling industry and as you read and research the gambling industry you will hear of many things and some of them are totally strange. As op has said we have seen people that collect money from others and trade forex for cryptocurrency and the end of the day they reward them with profit. But this system is not guaranteed in gambling because gambling is prohibited in some countries.
Apart from what I have said above. It can also be seen that you that is financing a gambler can be a culprit if the gambler eventually turns to be a gambling addict.
I would guess that something like this is very rare, since the gamblers that are really good not only have their gambling profits already, they can find other ways to make money, by either becoming an influencer and show to others how they obtain their profits or depending on their preferred game they could become sponsored by casinos themselves.
So a gambler looking for someone else to finance their gambling habit is probably not part of the group of successful gamblers, and most likely you will just waste your money if you were to give it to them.