He wasn't trying to damage Pitou tho.
Kite was weak. Thats why Pitou made quick work of him.
The royal guards didnt have great nen abilities for fighting and they were inexperienced.
Kite wasn't weak, he beat dozens of chimera ants and by the looks of the terrain and what Pitou said, he also gave a pretty good fight against her. Pitou even tried to revive Kite because she wanted to fight him again.
The Royal Guards are already born strong, their abilities is secondary to their raw power. Pitou was literally born a few days before her fight against Kite, an experienced nen user
At most Hisoka could stalemate one of them like Gon and the others did at the palace.
Netero wasn't trying to kill Pitou but that slap he gave her would have obliterated Hisoka breh
Gon had to sacrifice his whole potential and future to be able to kill Pitou, Hisoka wouldn't have done shyt with his Bungee Gum