From a traditional standpoint of winning the battle and taking the town that is obviously the case. But our objective isn't a total military victory. The keep is largely a distraction regarding our actual objective of destroying the food stockpile.<br/><br/>There's also the fact that 4/5 characters are predators to at least some capacity. We are here to have fun. Our characters eating people is fun. Characters attacking the keep aren't going to get to do much eating because of the need to fit back out the trapdoor. Not to mention that Lexikandrias simply won't fit through the trapdoor to begin with.<br/><br/>Though obviously this is a place where the adage "Don't split the party." doesn't necessarily apply. Lexikandrias has been implied to be the one in charge of torching the granary since she has magic to get it done quickly for instance. It wouldn't make sense for her to be tied up at the keep. Jayazi could oversee the forces at the keep if you and thus likely she feels that detachment is vital to the success of the attack as a whole.