I don't know what's so hard to understand.
This is not a series where the shonen hero defeats their arc villain in a single sneak attack.
Why that's not going to happen is irrelevant. Will Gon refuse to do it? Will she see it coming? Will she simply shrug it off? Maybe. The point is, it's not going to happen.
I guess I just don't care about why it's not going to happen. I'll find out when we get to it. All I know is it's not the resolution that we're going to get.
This is, of course, assuming that the plan is even to have Gon suckerpunch Pitou. Which it isn't, because, I'm not sure what you've been watching, but the plan is to use this power on the King, with someone more powerful than Gon.