My answer was "a teď my jsme muži." Why is it incorrect to include "my" in the answer?
It is a super unusual word order. I do not know if there ever is a circumstance when one can say that one or another word order is completely impossible in czech but this is close to it. Acceptable would be
A my jsme teď muži.
Teď is spelled incorrectly, the accent is missing
It is not.