When the dryer is on the ex-low (switch) setting the air should not be real hot with the inside dryer door being real hot correct?

Correct, it should regulate the heat at a low setting.

I notice that the unit has a heat switch.
Does it still heat up on the no heat setting?

Check the white/violet to white/blue to see if it is changing resistance at different heat settings.

Could be that it is blown (open) and then the operating thermostat always runs on high heat.