Failed: TASK [head-node : Ensure User SSH Keys]

On a hardware POD:

TASK [head-node : Ensure User SSH Keys] ****************************************
Tuesday 09 May 2017 12:01:23 +0000 (0:00:01.593) 0:16:01.009 ***********
fatal: [10.90.0.251 -> localhost]: FAILED! =>

{"changed": false, "failed": true, "msg": "useradd: Permission denied.\nuseradd: cannot lock /etc/passwd; try again later.\n", "name": "cord", "rc": 1}

The issue is that {{ ansible_user_id }} resolves to the remote user, but we want the local user. It works on CiaB because both remote and local user is "vagrant".