I feel it is open for debate I know there are ongoing studies with corns and UVB that are showing differences but it is unclear how important they are. however there is well documented ground evidence of royals out in the early morning sun and late afternoon. Nocturnal yes most of the activity is during the night but not all of the activity is.
The termite mound issue is a second partial myth. They are often found in some areas in termite mounds but living solely? No. It is easy to prove the population density in Togo of royals exceeds, termite mounds, by more than 50% so unless you believe royals to be social snakes, many living in one mound, half must be else where.
High humidity and poor air flow is KNOWN to be a cause of respiratory issues. Documented by some of the best known herp vets and researchers around. (Dr. J Rossi and Dr. R Klingenburg for example) There are other causes, and many guesses but this one is certain. Using restricted air flow and high humidity is begging trouble down the road.
The whole debate is actually fairly silly as there is a easy and simple option that is being ignored. humid hides.