The fact that anyone is…
The fact that anyone is actually treating this claim with even an iota of credibility is sad. There is absolutely no way you'd be able to attach rocket boosters to a car and have it be drivable AT ALL. You're taking about a rolling bomb.
And aren't Teslas electric? Rocket boosters require combustion. So you're going to fill up an electric car with jet fuel exclusively for the rocket boosters. Where are you going to get this jet fuel are you going to drive your electric car to an airport to fill up on jet fuel to then drive it on the street?