I did some looking on the internet and it seems not all the weep holes are visible. I wonder if they added the lip to protect the hole from getting debis and corrosion that might plug the hole. The pictures should help understand. The red line is the weep hole while the blue is the drain plug. Your picture is included showing where the weep hole might be located. Could be visible but for the extra lip.?????
If the engine or pump seal would fail I bet it would drip from the lip as the hole is not visible.