Thanks for adding the .git to the git server url in the announcement. the standard gitea, or at least the OOTB version that is packaged for nix, comes with those flags set. I tried the gitea nix package locally and it worked ngit. Maybe there is something i can do to make ngit more forgiving.
Discussion
The strange part is my http logs show multiple successful status = 200 requests from ngit and NO errors and ngit still fails. So I'm not sure where the problem is.