I'll tack on to this discussion, as I've been doing the same thing.

I've got Captain Rank, Odin, 3/4 of Salvage bosses and 2/3 of the ToAU bosses under my belt. I'm not sure if I just got lucky as hell, but Gulfurlur and Medusa were up when my party got to their spawns and checked on WS. It's been 3 weeks since then and I've been sack-running to Gulool Ja Ja's spawn every day since then in hopes that he'll be up. So far, I've had no such luck. I've even participated in Beseiged when the Mamool Ja attacked (without Gulool) and ran to the door after the event to await his spawn (supposedly an hour later). I wound up sitting there for 5 hours with nothing to show for it. Something is definitely wacky with that guy's spawn timer.

Can either of you confirm for me that these guys are actually supposed to spawn 1 hour after their respective Beseiged (assuming they don't appear and get killed during it)?