To explain his card game thing, He lets you pick a card that isnt Joker and King/Queen. Hed shuffle the position of the cards and let you guess of which is your card. Joker and King/Queen has significance: King/Queen gets you kidnapped while Joker gets you killed.
If you get to guess your card, hed leave you alone and gives you entertainment (Juggling,Jokes, magic tricks, etc.)
Heres something; He entertains the abducted kids in whenever location the cult is in now to make them feel better !!! [But he didnt abducted the kid shown tho]
Wait, so even after leaving the cult and regaining his memories Jack still has access to his funny clown shtick?
YEP HHHH Hes stuck with his silly clown abilities
He will go back to acting like Normal Jack but can pull out crap out of his ass at anytime if he wants to be goofy-- he'll be stuck with that till the cult thing gets solved in some way-