Sorry, but that's not any better. What you've described is using Google Maps as a secondary source, and using Google as a source, even as a secondary source to check something, isn't OK. And seeing people playing with their dogs there one time doesn't make it a dog park. To count it as a dog park, I'd expect there to be some kind of signage, or a fence, or something for the dogs to play on (like on the one you've mapped nearby as Woodgate Dog park). I'm still not convinced that this isn't just a patch of grass