Goof During Murder!

I just submitted this to the goof section, but I noticed something during Tomasz' murder at the beginning of the movie. When the murderer is pulling Tomasz on the chair with the bag over his face, for a split second you see half of the murderer's face and it is obviously NOT John Heard's character. I can't tell if it is the actor who plays Harvey or a stuntman, but it is not him.

Also, the murderer is wearing a blue shirt, and in the next scene the John Heard character is wearing a tuxedo with a white shirt. Although it is possible that he changed shirts, it is unlikely that he had "murdering clothes" on standby somewhere in the museum.