Steve Guttenberg's character, had it existed, would have been trying to expose Kirk, not as a man out of time, but as a charlatan, trying to cash in on the whales somehow. He would have made a last ditch effort at the hospital, and when he realized that Kirk and company were the real deal, that's when he would have come through in the crunch, diverting the cops with some ruse to let Gillian get away with Kirk and company in the elevator.
See, that's my thinking, that or reveal them as aliens, after some comedy scene having followed Spock or something.