Checkmate flat-earthers

They're playing fast and loose with the word "orbit". The ride goes to the stratosphere on a big bag of helium, generally referred to as a "balloon"

It's also a huge waste of helium, as helium is the only element that can escape Earth's gravity, and to descend they have to deflate.... so say bye to that helium.
Also, helium is a vital element used is a plethora of medical equipment.

They'll just say the "windows" were actually just LED screens.

Leave them there, then

Boy they'll be in for a surprise when they decide trying to go outside is a good idea.