Is it no longer possible to direct message a specific moderator?
I wanted to ask @Kareem. where the knowledge for the poker quiz comes from? Is it just information acquired
directly from a poker training site or do you actually study / play poker yourself?
You can message Moderators inbox and whoever is available on the shift will assist you.
As for the question to Kareem, as far as I’m aware he’s good at Poker and knows pretty much but let’s wait for his reply. He knows better 
My sources come from training sessions where various quizzes are administered. The answers are provided and explained after the quizzes are graded.
There are a few of them out there that you can use, you can search with Google and choose the one that works for you.