My Voron with its nighthawk is currently printing, so it’s gonna take some time until I can see how much deviation I get.
You have a spare ` at the end of your sensor_type, maybe Klipper falls back on a generic resistor?
Otherwise could the thermistor conduct some heat from the nh processor? (Maybe through the cable?)
This is what my temps look like after letting the printer cool back down again:
It’s a LDO Voron2.4 kit with the stock Extruder and the nitehawk board. The chamber thermistor sits on top of the stealth burner side door.
I dislike Discord as much as the next, but have you tried asking around if someone else has the same issue? Maybe you got unlucky and your nighthawk is defective.