(The whole idea seems a bit crazy too, there are a thousand things which can go wrong with a rocket, so let's look for snipers.)
He has convinced his shareholders that FSD will ship by the end of every year for the past decade, so why wouldn’t he believe he could convince the FBI that the only way his super fueling process could have gone wrong is via an action movie sniper plot?
If I didn't know any better, I'd say some guy who both roasted his brain with drugs and spends a lot of time in the company of a person who was sniped at is in charge of the company.
It exploding while just sitting there doing nothing narrows the possibilities 99.9%.