It might be that the view is referring to the parent view and getting the display style from that one.
I would try, bRet = swIsoView.SetDisplayMode3(False, swDisplayMode_e.swSHADED_EDGES, False, True)
I had tried that, but it doesn't work and the bRet value comes back false. I found this in the API help:
To display a drawing view shaded with edges, set swDrawingsDefaultDisplayTypeHLREdgesWhenShaded to True and set Mode to swSHADED.
But how do you set swDrawingsDefaultDisplayTypeHLREdgesWhenShaded ? Is that a user preference toggle to the solidworks app variable?
Ok I got it.
Dim bRet As Boolean = False
Dim bUserPref As Boolean = _SolidWorksApp.GetUserPreferenceToggle(swEdgesShadedModeDisplay_e.swEdgesShadedModeDisplayHLR)
bRet = swIsoView.SetDisplayMode3(False, swDisplayMode_e.swSHADED, False, True)
This sets the iso view how I need it. Thanks for the pointer on setting the parent view to false.