Happy Holidays everyone.
You are talking about the metal removable aluminum service shield right? This has combination of screws and mostly 1/4 turn screws. About nine or so. I think the screws are in the leading edge and the rest use clip tabs mounted on the plastic cover. maybe So you might need the tabs, 1/4 (or 1/2) turn screws, screws and the shield. For some reason the the screws are Phillips and the quick release are slotted. Your going to have jack it up to see whats missing. You have to see what else was damaged anyway but that area is surrounded by pretty heavy metal so hopefully that's all thats damaged.
Good luck. I feel for you. I hit my rims and about died!