I was in ther in november. Lots of frogfish and octopus. Not so many nudi's.
as for the rather poor codec of the Pen 5; that's not a big deal when shooting macro. After a few dives I got the white balance in line with the color temperature of the L&M Sola's. Correcting color was not necessary. I used manual expose alle the time, setting the shutterspeed at 1/60 en trying to get the exposure with aperture, a bit iso (340 max) and output of the lights. In Final Cut I tweaked the contrast and shadows/highlights a bit. Wide angle is a bigger challenge, but I think it can be done with the Olympus.
I didn't use a tripod, but put the camera tray carefully on the sandy bottom.
The most challenging rich was the goby in the last part of the film. The guide went totally nuts when he saw this one (magnificent shrimp goby). very rare and very shy. I had to put the camera in the sand, try to get the right focus point and then swim away at least 5 meters. Only after 10 minutes the goby and the shrimp would come out. When they disappeared again I could watch the footage, and try again. But on 23 meters air and time were running to very quickly. It took me 2 dives to get a few in focus shots