That's not the correct question to ask.
The insurance issue was only because Rock was already filming something (or just about to start). If he didn't have any movies lined up, then insurance would have been a trivial matter.
The Rock always has stuff lined up. Looking at his IMDB page:
San Andreas 2 - announced
Rampage - announced
Journey to the Center of the Earth 4 - announced
Journey 3: From Earth to the Moon - announced
Fast 8 - filming, released in April 2017
Baywatch - filming, released in May 2017
Jumanji - pre-production, released in 2017
Shazam - announced
From promotional stuff he'll have to do for Fast 8 and Baywatch at that time, to filming for one of those announced titles, to Baywatch, there's no way I see his scheduling allowing it without a studio needing to okay it and getting him the insurance.
Dwayne Johnson is an actor first.