Ok, let’s look at this theory:
Suspect buys ticket to get in like everyone else.
Suspectsits down near emergency exit door
Movie starts
Suspect gets up (uses phone call as “decoy”)
Suspect exists out emergency door (note suspects car conviently parked just outside exit door), before exiting suspect blocks door from completely closing. (ensuring he can get back into theater).
Suspect goes to car and gets suited up, loads weapons.
Suspect goes back into theater and starts shooting.
Hence, the “eye witness” did see someone and it WAS the suspect.
OK, there is a possibility the suspect blocked the door ahead of time as the eye witness described.
I agree that it probably was the suspect himself, going out and coming back. Remember, he had planned to have his apartment detonate at midnight, hoping that this would draw off the police so that when he did start shooting there would be nobody to stop him immediately. What happened, of course, was that the apartment did not explode, the police were at the theater, and in any case, his gun jammed.
I bet his next door neighbor is still shaking at the thought of what might have happened if she had pushed the door all the way open and walked into the apartment when the loud music started to play at midnight (he had timed it to go on at that time, when he would already have been positioning himself in the theater).
That makes sense