Unfortunately that is interesting! I am now intimate with my XYZ switch. Pulled it (apart), looked in reasonable shape but cleaned the contacts with wet and dry paper etc. All back in and no change in the symptoms. I noted that the switch has elongated bolt holes allowing some rotation adjustment. Rotated it fully clockwise and had an interesting result. Previously no neutral light or dash indicator but now when in the neutral position the reverse or drive light is on in the shifter and in the dash depending if it was selected from reverse or drive. Has not fully rid the flashing M&S but is a big improvement. I am curious about the harness, is that all the way from the auto computer? Do you remember the cost?

