Why does he use past tense for "got" here?
In informal situations, many people use "got" instead of "do you have" or "have you got" when asking a question. "Do you have" and "have you got" are grammatically proper and more formal, but "got" is still commonly used (particularly in America) when speaking. It has the effect of making a question sound more casual. Ex: Got any more chicken nuggets? Ex: A: Got a pen I can borrow? B: I don't have a pen but I've got a pencil.