The event looks like it is a force push (also know as new revision) of an existing proposal so it isn't displayed by `ngit list`.
The reference to the original proposal is actually a reference to a kind 1 event and there isn't an original proposal therefore it doesn't get displayed.
The event was almost certainly created with `ngit send` with the `--in-reply-to` flag referencing the kind 1.
`ngit send` does no checks to ensure `--in-reply-to` is actually a root proposal. This caused the error. This is a bug that should be fixed.
The language 'in-reply-to' is super miss leading. It is used because it replicates the functionality of the `git send-email` 'in-reply-to'.
There is a potential feature request here also. `--in-reply-to` should support referencing other events: kind 1s, issues, or even other things.  

 All it would need to do to fix the bug and add the feature would be to check whether the id is a proposal root and if not omit the 'revision-root' tag and potentially turn the 'reply' into a 'mention'. 

 @Laeserin do you remember if you used the '--in-reply-to' flag? 

 I did, yes.

I am determined to break everything that can be broken, but by accident. 🙈 

 well your doing a good job so far.
you used a pretty natural intuition on this one.  

 I was thinking it might be the basis of linking issues to different repos.

Like, I accept support issues on gitcitadel and then somehow link them to an issue on a different repo. 

 That way each development team just needs to keep track of their own issues, but I can make sure that the issues all get a fast response and are closed within a reasonable time. 

 yes, you should be able to tag a issue, comment, proposal or commit in proposal from a repository in a note (proposal, issue, comment) send to a different repository and have a reference to it and have it show up in both places.
Similar how it works 'mentioned in' in github I suppose. 
this is dependent on this issue and:
nostr:nevent1qqsg9fdqq7djq2sc7xamt49n7zd5qu73y8pupxfqxm3s76j3r25shqqhtk8jp
https://gitworkshop.dev/repo/gitworkshop/issue/82a5a0079b202a18f1bbb5d4b3f09b4073d121c3c0992036e30f6a511aa90b80
and  

 do you think that would adequately address the need?  

 Yes! ☺️ 

Anything more complex and you'd need a cross-repo issues board, or something, which would be cool for multliple-repo projects, but I wouldn't work on that until we get the kinks worked out or you'll get drowned in change requests.

Would probably need a change in the NIP to establish linked repos in an overarching project, or something. Dunno. 

 in ngit you can now tag as many issues, npubs or other nostr references as you want using the `in-reply-to` flag.
in commit 10498b953d36304b441fcb162155c2487046206f.
There is probably a feature request needed for gitworkshop to display these references nicely.