You could probably keep most of the action (if not all of it) intact, just make it a little harsher. The chain of events that happened in 1983 could still happen, in the same order, with the same people, but with the violence, and the effects of that violence, upped just that much more.
The easiest way would be to essentially have Fett’s pack go catastrophically haywire in a way that essentially “Anakin”'s him on the way to smashing into the skiff and falling to the ground. If Han hits him with the stick, it causes the rocket to fire and malfunction, and a charred and/or burning, almost lifeless Boba Fett goes flying towards the skiff while literally on fire, when he hits the side of the skiff, THAT can essentially be the point where the impact kills him. Have a minor explosion in the jet pack accompany the hit, and when he falls to the sand, he ragdolls down, the sand effectively putting him out just in time for his dead body to fall into the sarlaacs mouth.
I’m basically saying you can make Fett’s death PG-13 pretty easily with what’s already there, you don’t have to radically re-imagine the scene much. It’s sort of like how the Corridor Crew guys have been taking PG-13 action scenes from Marvel movies and showing how easy it is to make them R-rated with a few post-production flourishes.