Why is the guy white when he jumps in and bounces up and down but is black when he stops at the end and screams? Very odd.

What BS. If there was air resistance to start off with, you would reach a terminal velocity of 200km/h, not 28000km/h.

um, no. terminal velocity for a person would be about 200 MPH, or about 320 KPH. They would reach that speed about 12 seconds from the jump and their speed would not exceed terminal velocity without some means of propulsion. Their speed would not change their position until the passed the core where they would gradually slow down. They would not make all the way thru without some means of propulsion. And yes, the heat at the core would vaporize them before they got passed it.

Earth is turning. He would also scrape along the wall.

At four hundred Kilometers depth the air would turn liquid because of compression.