Will an RI happen if...

[NH93]

Other than the 74 spot the temps aren't grossly out of whack. Just some fine tuning needed.
As for humidity and, I am assuming you want to keep mulch as your substrate given your set-up, I just dry mulch/ repti-bark after rinsing the dust off(after removing excess water, the mulch I've found has less dust than the repti-bark so may not really even need the rinse) in a couple 5 gallon pails and a ginormous steel mixing bowl for a few days before putting them in the PVC enclosures.
In PVC the water bowl seems to hold humidity pretty well on it's own. With electric heat in the winter at most I've only had to mist twice a month.

Luckily I've had no issues with dust in the mulch! I do often have aspen around, as I find the corn prefers it (I use half aspen half mulch for her, so it doesn't get too moist) but I would think it would be too dry for the BP...?