If you look at the local version of the post at https://piefed.social/c/tesseract@dubvee.org/p/2232597/addressing-the-elephant-in-the-room, it has accepted a comment despite the original at https://lemmy.world/post/49817942 remaining locked. I do not see any comments on e.g. piefed.ca so the comment may not have federated.
Isn’t this a bug? It’s definitely going to be confusing to people, so I thought I would let you know! :-)
Edit: added details to title that the post was remotely locked on Lemmy, as opposed to locally or remotely on another PieFed instance.
When I open any of the links on my slrpnk account I get a 404, the same is true using the web interface.
On my piefed.social account using Mlem I can see the title, the author, that the post is deleted, and one reply.
Fwiw the original post in the first link was not deleted at the time I wrote my own post here. That may complicate discovery, though it may help to know that the reply definitely was added prior to the post being deleted.