It only takes one person misclicking a rejection reason for it to show up in the list. I would be more concerned about the “Other Rejection Criteria”. Memorial benches must be for someone significant as explained here:
I see in your supporting section that you call this person a “hero.” If you want to appeal this and give evidence to Niantic that this person is significant to the community, you do that through your contributions page. You get two appeals, each with a 20 day timer before you can use it again.
You could also try resubmitting this bench instead of appealing it. If you do, be sure to put a lot of information in the description about how Walter Tara was a local hero.