Yeah, I’m planning to replay it again with light side The Hawk's fate is different in the light side run, being part of the old tradition of canon endings being light side for the games while alternate ends are possible (such as Dark Forces: Jedi Knight, although that's more crisp clear with that ending, Jedi Academy being open-ended but clear). But if you have the Restored Content mod, a little more variation is shown and depicted than what the vanilla game had for that moment, making it beyond just a light side/dark side choice. The orders to destroy Malachor are, in this instance, thwarted by G0-T0.
Darksider's end is pretty much a dead end as you've witnessed, especially if it's in the vanilla game without TSLRCM.