It seems this edit is bugged, it’s been opened for 9 days and there’s no abstain or no votes. I remember trying to merge these two releases in my old account and the same thing happened.
I’m not sure what happened, but I see that it has been applied shortly after your post.
Sometimes if there is an annotation in the target it needs to be moved to the source. It’s an odd glitch that I’m not sure was the problem here but it seems to lock some edits into an “about to close” until either the annotation is removed or moved.
Seems like it may be this issue, which should have a fix currently in beta testing, so hopefully out on the main site soon: