Re: Great Moment.
I'm pretty sure that the Monitor tells Harbinger (maybe it was Pariah) that the death of some of the agents he was planning to employ has forced him to turn to the alternates. I seem to recall thinking it was pretty clear that he was referring to Ultraman and Power Ring, and that Superman 2 and GL were the alternates in question. I could be wrong; it's been many years since I read Crisis, and I don't have it in front of me.
But Ultraman knows he's flying to his death. He hears Power Ring calling after him, begging him not to leave him. Even if there really were no escape, nowhere to run (and again, the CSA knows of the existence of alternate universes) it would arguably still have been better to wait with Power Ring so that he wouldn't have to die alone. I just can't help but feel that Ultraman is kind of being a coward here.