Nothing Is Missing
But you do have a problem, the heater element should NOT be that HOT, the element box also shows signs of severe overheating.
You either have a clogged vent, Clog in the lint filter housing, very worn-bad rear drum seal and there are several other possibilities.
!st test to do is run the dryer with the vent hose disconnected to see how hot the heater runs, if the heater barely glows then you know you have a restricted-clogged vent system to deal with.
Keep in mind, the thermostat on the heater box should NEVER cycle the heater off if the dryer is operating properly, this is a safety back-up thermostat that only comes into play when something else is wrong.
Another thing to keep in mind on electric dryers, When a heater element or safety thermostat fails SOMETHING else is also wrong,
For safety and proper performance you must replace the bad parts and fix the problem that caused the parts to fail, under good conditions and proper installation a dryer should never need a new heater in its lifetime.
John L.