Whst external factors have they said it could be? Id definitely be speaking to Audi customer service. And it certainly should not have gone in 5k miles. When I've had issues with main dealers I get a second opinion from another main dealer. Alternatively I'd be getting specialist advice from an independent Audi garage for their opinion.
You could always contact the motoring ombudsman.
My advice would be to get the door card removed and then see what's moving. It could be the speakers, tweeters or electric window regulator all at a guess.
You might need a new unit if the led unit has failed. To find out which bulb you need you could remove the other light unit to see which bulb you need.
You could also get a diagnostic check to see if any fault codes flag up.
Yep it's a phone connector. You might have to replace the center console. Alternatively you could look at an aftermarket armrest from armster or similar.
It would but you'll need the powerfolding mirrors, motors, relays, wiring harnesses etc and it'll need all coding to the car. Autologics have been recommended by others for retrofits on here a couple of times.
If you've bought this from the garage in the last 30 days then you are entitled for a full refund or for them to repair it. It could be the rear light seals or boot seal.
Welcome to the forum you'll find the members on here are a friendly and helpful bunch ☺️ sorry to hear of your recent theft. Onwards and upwards though ☺️