Premise: I am not familiar with the book the movie was based on, so please forgive me if this is actually a plot point that gets covered in the novel. Also please notice that while I mention the movie, this question is specific to the novel since the problems with Sorrento plans seems to be far more explicit there.

Since I saw the movie adaptation of "Ready Player One" something has always been bugging me. How was Sorrento planning to get all the keys on his avatar and complete the final test? The movie didn't' go in much detail so I decided to turn my attention to the novel instead.

Based on a passage in the original novel the three keys that were needed to unlock the final challenge and "find the Easter egg" where "bind on pick-up item" that couldn't be traded in any way.

I wouldn’t learn until later that the keys were nontransferable. You couldn’t drop one of them, or give them to another avatar. And if you were killed while holding one, it vanished right along with your body.

This means that in order to get all three key an avatar has to complete all the challenges, and then the same avatar has to complete the final test. This... brings a problem. Let me explain..

At the end of the old videogame "Indiana Jones and the fate of Atlantis", Indy is used as a guinea pig for a machine that should turn humans into gods. He get out of that situation by pointing out how foolish is to test a machine that could give godlike powers on someone who would immediately use those powers to take revenge on you...

This seems a big issue with Sorrento plan too. It is safe enough to have someone else run his avatar to get the first keys, maybe even the third one. But as soon as you get to the "final" gate would you trust someone else to control your avatar knowing that they are about to get admin powers on the game?

And the final challenge in the novel doesn't seem just a character test like in the movie either.

In Halliday's Easter Egg Hunt, the first part of the Third Gate requires an avatar to surpass James Halliday's score of 728,329 points (on the videogame Tempest) in order to proceed to the Flicksync of Monty Python and the Holy Grail.

I am not really convinced that Sorrento could manage to complete that, even with support outside the game. But since winning awards you the prize, it would also not seem like he could risk someone else controlling the avatar at that point.

The very moments the one controlling Sorrento avatar gets the prize, they could cause a lot of damage in just a few seconds. Threatening the "victim" by saying that doing something unexpected would get them killed on spot doesn't seem much better either... it would probably only serve to make them realize that you are fine with killing someone, and would you really let one that knows you cheated live after they are no longer needed?
Worst case scenario, anyone who realizes that they are dead anyway could use those few seconds to shout out "transfer all admin power to Parzival" as a final act of spite and there is no indication to Sorrento or the Sixers that such a command would not work.

Therefore my question is simple: does the novel contain any indication that Sorrento had a plan to avoid that anyone completing the final challenge for him would attempt to "betray" him at the last second and do some last minute move that would crash their plans forever?