Sorry about the bad hatch.
I have a 9300, and am in my third batch. Great first hatch, mediocre second hatch. This time, I added the air circulator fan, so we will see how that goes. Pretty sure the mediocre hatch was a temp problem- I turned the eggs less often and I think the thermometers were incorrect - although they had been reliable the first hatch.
My first use of the 9300 I did turn by hand 3x per day. Wash your hands always before touching the eggs. Since there is inherently hot and cold spots, I removed the middle eggs, and turned the outer eggs and moved them to the center (just roll them towards the middle is fine). Then I replaced the removed ones to the outer edges of the eggs that were moved to the middle. So, always a new location in the bator. Took very little time to do.
Humidity. Too high throughout and eggs donāt loose enough moisture.
Room temp: try to have it in a stable environment. If not possible, then I have had success with putting this incubator (and a smaller homemade styrofoam cooler incubator) into a larger cardboard box with sides that are 1-3ā taller than the incubator. If you use a box, make sure that there is some excess room on all sides so air exchange can happen. A more simple approach is to get a large sheet of cardboard to prop up in such a way as to deflect the majority of any drafts. In addition, the floor is colder, so if you can put it on a table, or similar, that keeps it away from the coolest spot and away from convection currents where cold air drops and flows across the floor.
Good luck.