You should have power to the gray and red wires on the motor wire harness.
Most of the time if you have the correct voltage to a dryer and the motor does not run it's because of a bad thermal fuse or door switch.
Many times if the motor is bad it will still growl, hum or start hard, but you can tell it's getting voltage.
You can check the door switch and thermal fuse for continuity with a multimeter to see if they are good or not.
The MDE3000 uses thermal fuse part # 33001762
Here is a video that will show you how to check the thermal fuse.Thermal Fuse Help Video
Let us know what you find or if you have any other questions.