Scarlet frogfish is the common name for Antennarius coccineus. Diver's Den is better than most at ID, and in this case they are probably right, or close. I'm not great at ID, but I stick by my tentative ID of A. coccineus. There is a nice section on this species in the frogfish chapter of Reef Fishes volume 1. Try fishbase for some info, as well.