The zombie queen bee item is probably the best crowd-control weapon in the game. Simply shattering the jar containing a queen will kill all of the zombies near Frank. In fact, it's so effective you really don't need us telling you to stock it.
However, you should know that the appearance of the queen bee isn't random. In fact, you'll find one in every large group of zombies in the game. Just look for the undead soul that's looks like he has a major headache. Administer a sledgehammer beatdown instead of Excedrin. This will produce a queen every single time.