Wood pellet litter isn't the same as wood shavings, and isn't dusty like the kiln dried pine shavings can sometimes be. The pellet litter is in pellets, then expands when wet. So unless the expanded sawdust dries out and a rabbit digs around in it, then there's no reason it should be dusty at all. I actually found carefresh to be dusty, plus not very absorbent, compared to using wood pellet litter.
Talks a little bit about litter choice here:
https://rabbitsindoors.weebly.com/litter-training.html