Deliberate mistake: In one of the dogfight scenes a Japanese Zero crashes into a tower. It's a quick shot, but you can still see that what crashes is an American P-40 with Japanese markings.
Deliberate mistake: It's 1941 in a military base and no one is smoking...
Answer: He is in the scene where the smaller air-base is being attacked by the Japanese. You have to look really closely but he is the driver of one of the jeeps right before the Japanese bomb drops (the one that seems to be a dud and then explodes). Also, Matt seems to be one of the gunners on one of the first ships at Pearl Harbor to return fire (this is not verified but in slo-mo, one of the gunners seems to be him).