I don’t understand the mission at all. His goal was to build a rocket that would get to 40,000 feet to prove the earth was round? He could have chartered a private jet to 50,000 feet and saved a lot of time and money and taken his flat earth investors with him.
He was able to verify Newton’s law of gravity as well as the formula 9.8m per second squared.
There’s even a website for his investors to calculate the numbers. The Splat Calculator.