Have maintenance inspect the tray seating, tool mounting and finger contact with the equipment isolated for that work. Compare with the intended assembly. Keep a note of what they find before tidying it away.
Find why the replacement would not seat. Removing the washer alone leaves that question unresolved. The tool designer should review the pad geometry before the arrangement goes back.
Get the replacement reference sorted in stores too, once tooling identifies the difference; otherwise someone will helpfully order another pad that needs the same inventive washer
Include the old complaint in the eventual transfer check. A square-looking grip after the correct pad arrives would be progress, but your first pickup edit may have been addressing something else.