"Here's a useful tip to keep in mind for the future. If, at any point, you have the desire to run comparative siege engine projectile experiments involving oversized public transports and military aircraft, just do it."
Some further thoughts.
F-35 has 191kN of thrust compared to the Routemaster. Which does not list it's power in the datasheet. So to make it fair, we may need to add JATO. This would likely increase YT hits.
We don't actually need the F-35 and asking if we can launch the aircraft without it using it's engine is likely to lead to a swift showing of the door. Possibly at terminal velocity.
EMAL is inside Lakeland AFB. I doubt painting the bus Navy blue or OD will fool them. I also doubt telling any Marines on guard that you're testing a next-gen amphibious assault vehicle would help. That would likely result in lethal force being applied on the grounds of self-defence. They get screwed over by contractors enough already.
Mythbusters on the other hand do seem to be on good terms with the US military..