Architectural non-compliance issues

We have a homeowner who painted their garage a color that is not in compliance with the rest of the neighborhood as documented in our protective covenants. This homeowner did not get pre-approval via an architectural change request ACR form. The homeowner has already been sent multiple violation letters and is showing no plans to repaint. The Board does have the authority to fine the homeowner and hire someone to repaint the garage without the homeowner's approval (charging all attorney's fees, repair cost back to them). We have not gotten to that point yet.

The homeowner is now trying after the fact to get approval signatures from other homeowners to say their paint color is now acceptable.

Our covenants don't specifically state what should be done in this case, since an ACR form should have been submitted prior to painting. My question is, can the HOA Board deny any vote on this matter or reject the homeowner's request even if they get enough signatures from other homeowners? If they had gotten approval or enough signatures before doing the paint work, that would be a different situation. Is it legal to get signatures after the work has already been done and do we have to honor it?
There's no guarantee they would get enough signature anyways, but I want to be prepared just in case.

I appreciate any input!

-K Maz

Think about this: if a sufficient number of homeowners say they have no problem with this paint job, what purpose would be served by going to war not only with the offending owner but also those who signed off? What you are saying is that your ego is more important than anything else; that you are willing to win at all costs. Are you nuts? You are going to spit in the faces of the very people who put you on the board.

You also suggest that your board might have approved the colors had the owner asked first. So this issue is not at all about paint colors but about bureaucratic procedure. Have you thought for just one minute about how stupid you would look telling a judge that you have mounted a full-blown legal battle because the homeowner did not say, "Mother, may I?" before going ahead with something that no one else has a problem with?