Found the problem.
You can't use SQL Geography Types for offline Collector (Haven't tried SQL Geometry but I wouldn't be surprised if it doesn't also work).
Create whole new DB with SDE10.2.2 to find the same error. Created a new feature class with same fields and SDE binary and it works.
We use SQL Geography on triggers to do intersections with other featureclasses to fill fields post collection.
Now we have no shortage of SDE 10.2.2s... 😕