It sounds like KB (or its sub) may be liable to you, if it was performing the painting work and negligently caused damage to your car. Suggest you enclose your damage estimate or invoice with a letter demanding reimbursement. You may also wish to provide this info to your insurance along with a claim, and they will probably go after KB. If neither course works, you can sue in Small Claims court for up to $10k. Good luck.
This response is intended to provide general legal information rather than specific legal advice, and does not create an attorney-client relationship.