Although the playground seems public. Its just my suggestion but why not u mark where is the school area and fence in google satelite. That way niantic team can look into the case faster. This will be more beneficial for you since niantic team is not local and may not be able to see boundry as clearly as u.
I understand your frustration, but this is no longer the place to request portal issues. Wayfarer is now a Niantic/Scopely product along with Pokemon Go. Ingress is with Niantic Spatial. See below for the official announcement:
So what am I supposed to do now? Niantic Spatial has no space or feature to make any sort of appeal as far as portals are concerned. The place is legit, far away from K-12. And I have proven it on countless occasions, with geotagged videos, photos and other evidence. What is wrong with you people that you ban legit locations on a whim for the legit users that have been with your company and product for over ten years.