[X] A couple of discrete agents to smooth things over would be helpful -[X] Not for combat, but to keep mundane law enforcement away and prevent masquerade breaches. Possibly to take mortal cultists away afterwards too.
[X] Thank her for the offer but this will be easier to handle with a small team -[X] This operation has already gotten messy. While we don't need her agents for what comes next, ask her to be ready to help contain the aftermath. The enemy have already brought military grade weapons into the conflict and are planning to use nerve gas. Who knows what the final result will be? Whatever happens, they are going to need a plausible explanation ready for public consumption, including those authorities not read in on the supernatural world.