Maybe the chat option doesn’t respect filters in the settings (like hiding bot accounts or your specified language)?

It looks like the two missing comments are replying to a deleted comment -- you can see this clearly from kbin.social here: https://kbin.social/m/thepoliceproblem@lemmy.world/t/567779/St-Louis-cop-who-shot-up-a-kids-trick-or-treating-event

Maybe there's a bug with how Lemmy handles threads involving deleted comments?

Edit: There's an issue open about this bug already -- https://github.com/LemmyNet/lemmy-ui/issues/2133

While I didn't have the exact same problem, I did have issues seeing all the comments on any given post. If I was signed out I could see them all.

I went to the instance setting in my browsers (not an app) and changed the language settings to include both the default (unsure of that's what it's called exactly) and English settings. I haven't had an issue since.

Hope that helps!

Might be worth noting that if I click "New", "Hot", or "Top" I see the same 2 comments. "Old" shows me zero comments. "Chat" auto-selects "New" and flattens out the comment hierarchy showing all 4 comments.