I'm not sure of the etiquette of this site so I'm just going to point out at the beginning here that this post will have spoilers. I'll edit this part out if I am informed that spoiler warnings are unnecessary.
In episode 107, Palm is caught by Pitou's En while on a mission to infiltrate the castle and catch a glimpse of the king and his guards. Her power makes the tactical advantage of accomplishing this mission obvious, but it doesn't make much sense from a planning perspective.
The Hunter association was aware of Pitou's ability to detect intruders at tremendous distances. They also knew that this ability was in use around the castle; evidence being that Knov's comment about the En barrier being unexpectedly lowered, thus allowing him to place portals in the castle.
With this in mind, it seems that there would be zero chance of Palm succeeding in her mission; at best she is made useless by being trapped in the underground compound, and at worst she is captured. The fact that they chose to send her on this mission is baffling to me because the characters in the show usually engage in an extremely detailed risk analysis for important decisions.
The only thing I can think of that would make sense from a planning perspective is that they cynically counted on the team's sympathy for Palm to get them fired up for battle when they discover she has been captured. In other words, a sort of artificial morale booster.
Can someone provide a plausible in-world justification for this mission?