Left a response in the linked thread, but am copying it here, too:
From my view the original comment has been replaced with "deleted by creator". If a user deletes a comment in Lemmy 0.18.5 then it and all its child comments are removed from public view. Though @[email protected] will still see their own comment in the comment history section of their user profile. I think that this behavior will change when we upgrade to 0.19x, and non-admin users will see "deleted by creator" as well.
There appears to be something else going on, too. If you view the post from lemmy.ca or literature.cafe (both of which are on Lemmy 0.19.1) the original comment is still there. It's like those instances never got the memo that the comment was deleted. I can only assume this is related to the ongoing federation issues in Lemmy 0.19.x?