You could simplify it by splitting it into two sentences or choosing a simpler structure.
I�m collecting the (GROUP) family. Do you have the (MEMBER)? --> Yes I do / No I don�t.
I would like the (MEMBER) in the (GROUP) family. --> I don�t have that card. / I have that card.
The easiest option is: I would like (MEMBER) (GROUP). --> I don�t have that card. / I have that card.
So your dialogue would go like this:
Hello. I would like Mummy monster.
Sorry, I don�t have that card. I would like sister zombie.
I have that card. Here you go. I would like Daddy pumpkin. (etc.)
With this activity, make sure that you model it really well before starting, and that all the key structures are written on the board for the pupils to refer to during the game. You could have a rule that if they speak their native language at all, they have to forfeit a card to the person who calls them out.