I can confirm the row 3 interference for ePBT ABS sets, though I don’t know if this is a result of stem length. Also the ePBT dyesub PBT standard homing keys which are barred and scooped, interfere with switches regardless of their orientation – some sets may have separate molds for each, but I don’t know for sure.
Solutions that work for north facing switch interference could help here to, namely the interference washers if you can find them in your region.
I know two of these stacked removed the ePBT ABS interference.