Hi Matthew,
How are these cells being generated? If the detail cells have been automatically generated using their own class definition, then they will automatically have their delegate set to the uiElementDelegate of their class definition. If you have created these cells manually, then you should set their delegate yourself.
Also, you can loop through the cells of the detail model and assign their delegate in the tableViewModel:detailViewWillAppearForRowAtIndexPath:withDetailTableViewModel: method.
Hope this helps