Vicks on tooth surfaces will lead to swelling and further complications. Not suggested.

Vicks is not for ingestion. Please do not put in her mouth. Ask her to keep a clove in her mouth where she has pain & leave it there for a short period. Clove is a well known remedy for cavities. It's better to avoid sweet stuff, but if she does eat sweet foods, she should make sure she's brushing her teeth before going to bed. Make an appointment with a doctor to get the cavities filled in so that food doesn't get stuck in there & make the cavity worse.

I suggest visit dentist

Gargling with Salt in Luke warm water helps temporarily. Put ice pack only if she has swelling. That too not continuously. On and off. And please visit a dentist as soon as possible before the problem becomes big.

Give her a small ice cube. Please visit a dentist. Meanwhile give her salt in hot water. Tell her to keep it sometime in her mouth and swish it where pain is there. There will be temporarily relief.