| Lost In Limbo |
I know it's a bit pointless, but I'll chime in with an "I don't think so?".
The question is, does Vermin Empathy (and Wild Empathy, and Diplomacy) only target one creature at a time or can you use it on groups?
If you can influence groups at a time then obviously Vermin Empathy would work on swarms. However, most of the language seems to indicate a single target.
As an aside, I would totally allow it in my games, but this is the rules forum after all.