Epicor changed the behaviour in E10 because when GetList and GetRows both got the same data it hit performance… So by keeping “List” slim to Essential Columns, they improved alot of performance.
So yes, you will have to change the EpiBinding to InvcHead instead of InvcHeadList - Looks like in that form they decided to use the same EpiBinding they use on the Navigation Control all the way up.
If you are a developer and want to read about .GetList / .GetRows: