Brand new Prusa Mk3 hotend and thermistor replaced with Mosquito, temp runs away and melts print head

Brand new Prusa Mk3 hotend and thermistor replaced with Mosquito, temp runs away and melts print head

Well the title says most of it. I printed the needed pieces from thingverse to install the Mosquito into the MK3. Everything went well enough but when I try to run the PID calibration the unit runs away, Prusa display never says it goes over 240 but the PTEG fixtures holding the hotend start melting and turning white.

When I run the self test the unit says all good!

When trying to load a filament and heat to 240 for PLA the unit gets to 150ish and beeps before aborting the load with no errors.

Any idea what I am doing wrong? is my hot end defective?