Won’t Commit Fraud? You’re Fired!
Usually, the only people you charge for your services are clients. Anyone else who has no relation with your business—your dog walker, the gardener, or your second-grade teacher—will not receive a bill in the mail for something they didn’t ask for in the first place.

However, that wasn’t a good enough reason for the OP not to send an invoice to a total stranger. Because the OP had integrity, the company decided they had to part ways. “If you don’t commit fraud, you’re out of the job!” We honestly hope that the company’s misdeeds caught up to them.