Hmm… So you have tried a couple of times now, and both nominations surprise me in being rejected by the automated process. Maybe it is time to try an appeal. Pick whichever one you like best. (I think the most recent one looks most inviting.) I do not promise it will be accepted, but at least you can make the case you have made here about it being an important social space. The clarification is for picnic “areas” being eligible as a social space:
We get 2 appeals, each on a 15 day counter before we can use them again. Let us know how it goes if you do.