Incubation is very much about experimenting and working out what works for your set-up and climate. Despite high humidity in my climate I still need water in my incubator, otherwise the humidity gets too low.
I would bump up the temperature and see how you get on. In a still air incubator there are layers of different temperatures, whereas there's less temperature difference in a forced air incubator where the fan is constantly moving the air.
Do rotate the eggs to different positions in the...