You really need to keep the fan running here as the power supply and display put out a fair amount of heat.
At this point you’ll need to check the fan’s thermal sensor is it plugged in and the cable is not damaged? When you have an open the fan will race. Also check the back of the display its self there is another thermal sensor on it that is wired to the T-CON board on the back of the display (covered by sheet metal). Also inspect the displays LVDS cable which you unplugged from the logic board is it damaged in anyway?