This specific tension happened a lot sooner than I expected.
Let's see... a guy famous for (among other things) owning a company that builds electric cars teams up with the guy who said he wants to outlaw electric cars. Fireworks were inevitable at some point.
I don't think EVs are the key issue here. The key issue are the grotesquely overinflated egos they both have. It's basically impossible for them to accept anyone as equal.
No it's a guy who wants to be king vs a guy who wants to hold the whip but both view themselves as heroes and the greatest gift to humanity.
One thinks his personality is what won him over and will keep all the support of his followers and one thinks he's the smartest person in the room and his correctness will show that he deserves all his followers.
It's cult leader narcissist vs cult leader narcissist. They don't even have to get to policy before the breakdown occurs.