Adult dragons who prefer hotter tanks

I have a female dragon who has been slow and sick for a looong time. I am on vet #2 and one recent suggestion was upping the cage temps even though they are warm enough, though on the lower end of the suggestion spectrum. I keep the basking area around 103ish and the floor at 80. She will do the open mouth, "tis hot up here," thing in the basking area, sometimes, so I figured it was a sign she was toasty enough, at least there.

So, for those who keep their adults a bit warmer, what temps do you go for? I bought another light a couple of days ago and have been slowly making adjustments. I have probe thermometers but I did order an infared a few mins ago so I will have that in a few days to use as well. I also bought a hammock to give her a different heat option besides the branch (it's large and varied in height) and floor.

I give my guy a spot that's around 115-120, and another around 100. He shuttles between them and the unheated areas.

Gaping is more linked to brain temperature than core temperature. Does your setup give an evenly warm basking area the size of or larger than her body? How big is your cage? IMO that's one of the factors that limits the heat you can offer. Too small of a cage and the ambients will rise too much.