Not as familiar with the gamebook limitations vs the text adventure mode, but I don't see much of a reason that it shouldn't work. There are several ways to create a random chance of something occurring, add that into a scrip that runs when you either move to a certain page, or even within the link itself that is disguised as a normal "to next page" button.
At the same time there's the whole thing about making a text adventure that mimics a game book in what the player can see.
A quick example would be just using the built in
RandomInt function.Something like this
*disclaimer, this is quick and very likely inaccurate coding, don't expect this to actually run if copy/pasted into quest*
//this script causes a random split in the resulting page
random_number = RandomInt(0,100)
if (random_number < 30){
goto page 42
}
else {
goto page 578
}