Other mistake: When they show the comic book and Hiro looks up the artist's address, it is listed as 215 Reed St. 7. The door to the artist's loft says his address is 681. (00:01:10)
Other mistake: After Peter falls on the cab, a piece of metal is sticking out of his chest. He pulls himself off it, but when he's on the hood, the piece that was sticking though him isn't there, even though it should be visible.
Other mistake: When Niki looks at the Cadillac's registration, it says the license plate number is "307RTH." When she opens the trunk, you can see the plate and it's "329OCX."
Chosen answer: Hiro's powers are still quite unreliable, and a locked closet door isn't a huge obstacle. Since Hiro knows he needs to rescue Ando, it's probably safer to try and bash the door down than risk teleporting to the wrong place or time.