giacaches: I went over and checked on this one after receiving the notification of a DNF from Bird Nerd. As noted, the cache is MIA. It seems the city has decided to do some different landscaping at GZ than in previous years and the cache was directly in the way. I'm assuming someone from the parks department picked up my cache when they were planting the flowers.
Oh well, it was the first cache I ever hid - and despite having permission to place it, I think I learned a lot. I'll hide a new one in this park soon! Thanks to everyone who found it :)