I took my bumper off today to have a look at fixing the fangs, and found that the whack which caused the damage also seems to have broken the mounting on the drivers side! The two points on the wheel arch under tray have come clean off, and there's a piece missing on the main under tray around where it fixes on the right side
So, did anybody ever get a price for the wheel arch under tray #51718046084 I think? I think I can live with the main under tray, as it still has 2 points where it's attached, although I might try and patch it up.