hehe they might just find a way (but you should be pretty safe)
well just to throw in my 2 cents (granted it doesn't seem to apply to your problem, KDoods), i've been lucky enough to grow a few D. nidiformis long-term for 3 years now (under lights) with several plants never dying on me. However, i did have some problems when i grew mine under a shorter 9-10 hour photoperiod and gave it a bit too much water. They seemed to experience the fungus issue, but once I cut back on watering, increased the photoperiod, and gave them a better-draining mix (about 2 peat: 3 sand, packed down), they never had any further problems.
Not sure what your pot size is, but i use a 4-inch pot. Assuming you're using something similar. Also, I did see another grower with the fungal-related issue on his Nidiformis when he had it under bright light intensity, but forgot to water it a few times (was not dessicated though). Otherwise, your conditions sound great- possibly just a bit more humidity than mine get, by about 20%...
To be honest, I've neglected mine as they rarely get fed (maybe once every 3 months) while I'm away at school. So they generally only keep about 4-5 large leaves going at a time. Then when i get a chance to feed them, they go crazy, flower and then go back into the slow growing stage til i feed them again...
Anyway, enough yapping for me. I might as well post a few pictures after rambling on so long...