Other mistake: During the scene when Miles is in the hotel room asleep while Jack is out with Stephanie, Christine calls Jack on his cell phone and then on the hotel phone. First disturbed and awakened by Jack's cell phone ringing, Miles gets up to check it to see who is calling. He sees that it is Christine calling, and then lays back down. The cell phone shows Christine calling and then IMMEDIATELY afterward, it says that there is a voicemail waiting. That certainly was an extremely short amount of time in which to leave a voicemail.
Other mistake: Miles' residence resembles apartments found in Mission Beach, which is north of San Diego Int'l Airport. In the scene he was allegedly heading home, driving south, but passed the turnoff.
Answer: Miles himself answers this question in the film. He tells Maya that he could have made something up, but chose to tell her the truth because he respected her and didn't want to lie.