With Dean’s particular skill set, that’s never been an issue. If he ever locks himself out, he can break back in without a problem. He’s a master at picking locks and stealing cars, and now he’s got a four inch brother who can even get into the walls and practically vanish if he needs it. (You can definitely lock yourself out of a motel but the front desk can usually get you in without a problem ) 

They will get in, I guarantee it.