Was a solution ever found for this problem? We're having the same issue with an ArcGIS Server feature service with Create, Delete, Query, Sync, and Update capabilities enabled.
We can create new features in Collector but in ArcGIS Online web maps and web apps, when you click to add a new feature there is a blue status bar and then nothing happens.
We've confirmed that the edit operation in the web map and web app do not commit new edits to the database (we thought the symbology or feature templates may have hid the point after creation but that's not the case).
Totally getting the same thing...……...Do you recall what the problem was?