Maybe an insulating layer of ensolite foam on the bed platform to keep the surface a little warmer and above the dew point, followed by hypervent or froli springs would work to prevent condensation all together?
Our FWC mattress bottom is vinyl. I’ve never noticed any moisture, but it seems many others do. Wonder if there is moisture inside the mattress?
From reports of people who's mattress is tight against the overhang bottom would indicate that moisture is being driven through the mattress. So yes, the mattress has moisture trapped in it.
Even at home I leave the bed unmade for a couple of hours to let the mattress air out.