Is there a proper way to vent a garage into an attic?
My understanding of building code relevant to the US is that an attached garage area must provide a fire barrier (not firewall) from any living space. A quick search shows how effective this regulation is at preventing relatively serious garage fires from engulfing a home. Piercing that fire block and providing a direct path to the attic is a terrible idea.

Consider applying for a variance with your HOA to allow for a garage vent. Spend a few dollars with an architect or contractor so you can include detailed design plans with your petition. Most HOA charters will require the board to either approve the variance or respond with necessary changes they would be willing to approve. I have never seen an HOA board outright deny a reasonable and detailed variance request.

It may cost a little more up front, but the results will ensure you can resell your home and could even save your life.