Before a new training sheet calls this distortion, I would ask quality to compare the checking fixture with the current part drawing. The old instruction may be teaching people to satisfy the wrong object.
Then the old correction instruction sounds particularly expensive. Has anyone checked whether that rear lug changed between drawing versions? Not saying it did, just a fairly small comparison to make now
That explains why the experienced operator was quietly ignoring the nest while the relief operator followed it. Give them one agreed replacement instruction, otherwise the old habit wins whenever the updated sheet goes missing.