Andrew, did you ever figure this out? I'm having the same issue.
The point appears as I am collecting it but if I open collector again it is gone, it does appear on the web map though.
Sorry for the late reply - the new Esri notifications aren't doing a great job.
Anyhow, we couldn't get it to work, so the idea was eventually scrapped. I also left that company a couple months afterward, so I have no idea if they ever got back to another attempt.
I know we had issues with the data not loading properly because our AGS' Web Adaptor sat behind IIS basic authentication. Despite allowing editing to our map service, the IIS security still gave us issues.