Hi,
You can hear the whining of the PWM.
So the fact that you do get "some" motion is good but I would say its a lack of current for the motor.
That motor looks like a battery drill motor and they are hungry for current, more current than that puny motor controller is rated at.
What current is your power supply rated at?
Can you adjust its current limit?
At the end of your video, the supply looks like it is going into current limit.
A Lipo battery has some serious grunt.
I would say the motor controller is not powerful enough.
Can you measure the motor current when it is connected directly to the Lipo, put your meter on the 10A range.
Thanks.. Tom... 
