Definitely looks like predator got them to me. I found one similar in our orchard a few years back.
Had a weird one a couple years ago in our back pond. The wife called me over and said there was a duck egg in the pond, I walked over and it sure looked like a turkey egg but that was very strange because it was late August. It had puncture marks in it so I cracked it open and sure enough a dead little turkey poult in it. Only thing I could figure is a racoon lost it in edge of pond and it was maybe a third time attempt at a re-nest?
I like it way better when I find nests like this.