Yeah, and so what? We thought Trump becoming President was "exceedingly unlikely", too - and then it happened anyway, thanks to a bunch of Russian propaganda and a literal ton of dark money.
Who says that the richest man on the planet can't set up a lobbying/propaganda operation to secure him a shot at Presidency too? Especially a man who has a lot of very vocal, very dedicated fans all over the US? Have them e-mail and call bomb enough representatives and he'll get his will.
That would be incredibly ambitious; getting 40 states to agree to that seems exceedingly unlikely.