Hey man I made a thread similar to this, same issues. I tried air layering. It worked mostly but then along the way it somehow died. Nevertheless I did it, but in the mean time I got good advice similar to yours.
Basically I was told to add warmth (heat mat or warm window sill) only sprayed the dome not the actual plants, and I used root riot cubes and gave up with Rockwool. I sprayed the cubes I didn't pour water over them in case I washed away the rooting gel and powder