I have two different Mazar-i-sharif crosses in the Mamma Mias and the differences are quite subtle. But, they are two different creatures. Collette is a stinker and is more stretchy. Helen has tighter nodes and wider leaves. As time marches forward. As time marches forwards, the differences are more evident.
Right now they are out in the greenhouse where it is 87 degrees and 18% RH. The floor of the greenhouse is indoor-outdoor carpet. I keep it soaked with gallons and gallons of water. The carpet dries, but the RH never goes up much. Growth rates are crazy. I have a top rated humidifier I've tried using in there. It does nothing.
Based on my limited experience, the strain doesn't seem to mind. I suppose that trying to add some moisture to the air isn't a bad thing. I'm doing it - with limited success. High altitude sunshine with little water vapor available - is what it is. It will get worse as temperatures drop outside... What moisture I introduce gets sucked away quick! The atmosphere is a big place.
Hell, I'm not growing a "tropical strain." Part of your mother search involves finding one that kicks butt in your growing conditions. Selecting the mother that does best with low RH should be a priority. There is enough to worry about with medium, feeding schedules and light.
I propose you select the mother based on what she does under low RH instead of devoting heaps of energy into raising the RH of the grow environment. Don't try to ram a square peg into a round hole.
But, what the heck do I know!