I have the same problem! Wanted to put my eggs in yesterday but even with no water, it was still in the sixties! Mine are in the basement too and the dehumidifier is cranked. I just now took the lid off, put the eggs in, and am hoping for the best.
Edited to say: it should be ok to pull them out and dump the water. Here's a trick I used last hatch and it worked great: get some plastic aquarium tubing. Poke a hole through the outside of the bator and feed the tubing into the main well. Use a pencil to poke the hole and to flatted the lip of the well so the wire screen lays flat against the bottom. I use a syringe to add and remove water as needed and never have to open the bator until day 18.