I agree that if he weren't seeking public office, this probably would have gone unnoticed. But those rules are well known among anyone who has taken an engineering education and others have been similarly sanctioned for misuse in the past.
The correct course of action upon receiving a misuse / cease and desist for referring to yourself as an engineer is to apologize, issue a statement clarifying your status, and stop referring to yourself as an engineer. For someone seeking public office to assert that the rules don't apply to them... that's a bad look.
The correct course of action upon receiving a misuse / cease and desist for referring to yourself as an engineer is to apologize, issue a statement clarifying your status, and stop referring to yourself as an engineer. For someone seeking public office to assert that the rules don't apply to them... that's a bad look.