The video itself say's that they often shot the fuel trailer and not the tank.

No 50 cal can penetrate a tiger or king tiger tank, anywhere except MAYBE in the grill/vent on the engin deck. This would almost never cause the tank to blow up and would just immobolize it if you are pretty lucky.

Tiger kills were often counted but in fact they were Panzer IV's with the skirts.

You are better off dropping a bomb or shooting rockets at it, that's how you kill tanks from the air.