I actually just went through the same thing with chicken and pheasant eggs. They were supposed to come within a day of one another and the pheasant eggs were delayed. I incubated normally until the chicken eggs needed to go to lockdown. I managed to put the pheasant eggs in an area of the incubator that was easily accessible from the side so that I only had to crack the incubator open a tiny bit. I did not mist the chicken eggs at all when I turned the pheasant eggs, I moved very fast and the humidiy didn't budge. Once I had my first pip, I fashioned a coat hanger by bending the end so it was blunt and went through a vent to turn the pheasant eggs. My motivation was that I really wanted a good silkie hatch and wasn't going to risk opening the incubator after a pip. I was lucky that 4 hatched within 18 hours and I was able to resume hand turning the pheasant eggs pretty fast.
I candled the pheasants and all looks great.
Good luck