Permissions error with ssh key authentication to remote

I am using git-annex to set up a file distribution system with git commands as the interface. I have configured a unix user account with .ssh key so that calls to the git remote are authenticated automatically. I have set the ownership and permissions for that user account. I can ssh into the remote with that account no problem. But when I run git annex get to retrieve the source data from the annex, I get a typical permissions error. I have tried chown'ing and chmod'ing many combinations, but always get the same error. Looking for help to diagnose and fix this issue. Let me know if there are other commands I can run to hone in.

> git ls-remote
Warning: No xauth data; using fake authentication data for X11 forwarding.
From username@distro.myserver.edu:/path/to/remote/repo/.git
f4d9c5e4735f4c6b057d0c43090c80c09b7ab9ae        HEAD
49b3b4c81c3ce78443bb00c594cce51a4fa2c034        refs/heads/git-annex
f4d9c5e4735f4c6b057d0c43090c80c09b7ab9ae        refs/heads/master

> git remote -v
origin  username@distro.myserver.edu:/path/to/remote/repo/.git (fetch)
origin  username@distro.myserver.edu:/path/to/remote/repo/.git (push)

> git annex get sub-STJ82860572941V0120181112132504070/dwi/sub-STJ82860572941V0120181112132504070_dwi__dup-10.nii.gz
get sub-STJ82860572941V0120181112132504070/dwi/sub-STJ82860572941V0120181112132504070_dwi__dup-10.nii.gz (not available) 
  Try making some of these repositories available:
        fcfe03d6-3638-4ae2-baca-67c4c28e74bb -- username@myserver:/path/to/remote/annex
failed
git-annex: get: 1 failed

Cross post: https://stackoverflow.com/questions/53418582/permissions-error-with-ssh-key-authentication-to-remote-git-annex-get-file