Well, I've had the unfortunate and dubious distinction of having had to deal with some of these perverts and I know for a fact that once they get what they think is the "scent", you literally cannot drag them off of it.
There is no need for anything that would even hint of an entrapment.
These dumb SOB's will bring the trap, set it, and then stick their own, er, uh, hand in it, so to speak.
They will fly or drive hundreds of miles to meet with the child, once they get the idea in their mind.
They are not the brightest people in the world.
The DUers were actually discussing this the other day. Apparently, it's a big worry for them.
Entrapment is pretty hard to use as a defense if the perp is the one suggesting the meeting.