It’s been a number of years since I did this tour but all rooms had hair dryers. In fact every tour room since then (and there have been lots!!) had hair dryers.
I would check with the office on the particular timing for your tour departure. On my tour years ago we finished the boat tour about 530 down in the red-light area so it would have been a pain in the neck to get back to the Van Gogh and also not enough time before closure. Now I don’t think tour groups are allowed to go thru the Red Light district so timing may be different.
Any chance you can arrive a day or two before?
If not I’d give up the boat ride to see the Van Gogh Museum. BTW, I recommend you start by taking the elevator to the 3rd floor where the “good stuff” is and working your way down.