Oh my! A new monster! I sure hope it is playable!
The brood keeper's special traits don't do much to help here. The ability scores are horribly underwhelming for a 22 HD Huge creature (25 strength???), the special abilities are horribly outdated (Fear, Rake, Rend, Improved Grab).
The best thing about the keeper is probably that it gets pounce, but so do a 3 RHD monster race or a barbarian dip. Evasion's also kinda neat, if only because area spells are the only way attacking this thing is worth it over more dangerous targets.
Finally, their signature ability: releasing a swarm of larva. The larva themselves are mostly useful as mobile Distraction causers, and are remarkably durable, but all it takes is one stray spell and you lose one of your few racial features for a month. At epic levels, where there's barely any travel times, 'a month away' may very well mean 'halfway into the next adventure'.
Fast healing, SR (laughably low at ECL 22) and DR don't help: the brood keeper is simply a bad monster because of its massive amount of RHD, and deserves -0 LA.
Brood Keeper Larva Swarm
It's a swarm, but that's it. The larva aren't even Tiny, so weapons will still harm them, and their offensive presence is next to none. Not worth spending 22 levels on, -0 LA.