Continuity mistake: When Cross is seen inside Hank's home, he is wearing black gloves, a few moments later, in the same scene you can see that he is not wearing them anymore.
Trivia: Garrett Morris makes a cameo as the man in the car when Scott hits its roof. Morris was the first person to portray Ant-Man in a 1979 sketch for Saturday Night Live called Superhero Party.
Chosen answer: They could have opened it with a crowbar or a Jaws of Life. (Likely the crowbar, since we didn't hear metal rending).
Captain Defenestrator