If you go deep enough there are threshers in that area most of the time. I believe you can bring lights except at that one specific site they go to very early in the morning. I never brought any (lights) but I'm pretty sure the no lights is just for that one restricted area for the very early group dives. The entire shoal had Threshers on it most of the time, not just that specific plateau in the morning.
The threshers were present every day I dove there (in the shoal area). There are no lights or flashes allowed in the AM dives that are specific to threshers. I was on a rebreather and they would approach me quite closely. There was a lot of particulate in the water and the only footage that came out really well was shot from less than 6' away or so. Viz was good but it was always kind of hazy, and they are pretty deep so light was an issue.
The Dugongs were off Busuanga Island, the North center area. There is a dive center there called Dugong Dive Center they can arrange trips to the areas with dugongs. There is a "Dugong police" guy who has to go with you. There are several dugongs in the area but most are very wary of people.