A person can be intelligent and yet not good in gambling, and likewise, a person may not be intelligent but yet good in gambling, so it's likely vice versa, as gambling alone can never be seen as a factor alone to determine one's intelligence. Hence, I think getting the full definition of what "Intelligence" is will give us a clearer view on if will the game one gamble on reveals his/her level of intelligence.
So according to Oxford Google Dictionary, "Intelligence is defined as the ability to acquire and apply knowledge and skills"., and as such, to be able to be good in any of these gambling games, it's a must one needs to have good knowledge of it, which could also be called "intelligence", of which you having a knowledge of 1 or 2 do not determine the level of how intelligent you are