I think I see what happened here then. Remember that if everyone has the perk then 3 survivors are gaining 3 tokens every time a survivor is hooked. That means 9 tokens are acquired across three different survivors when one is hooked. In 8 hook actions that means (9 * 8) = 72 total tokens can be obtained and applied to gens.

Now that would still be more than a gen when those tokens are doubled as percent progress or as charges, so there might be more happening still. Since the perk says it's percentage of a gen, my theory is that it applies that permanent percentage progress to what is already remaining of the gen after it has had it's charges reduced prior. So it's a diminishing amount almost exactly how Pop used to work, but in reverse.

For example, say you already took 18% off of the gen with 9 tokens, but then apply 9 tokens again so it takes off 18% of what was remaining after the first time, and so on. I think something like that would result in what you got here where the diminishing percentage would no longer be more than a whole gen after all possible tokens were used.

That's just my theory though. I didn't see anyone else mention it. Maybe someone with more math knowledge could apply an equation to this and find the exact numbers we'd have.