Garage in south west recomendation?

[dannyindevon]

I have an A4 Avant, B9, 2016 reg. Bought in 2020. Have replaced the underside four times, and its just fallen off again, this time a small puddle did it. As soon as I got it home from the dealers I thought the middle dangled a little low as the 5cm tall grass in the middle of our drive was brushing it. 1st time it fell off was after 3 months, wife hit a puddle and the left side fell off. I checked dash cam and height of puddle against curbs, it was about 7cm deep and about 4m long, local garage screwed it back in place with some extra washers, said it was fine, £150. Still hung low, at next service I mentioned that you could see it parked next to another Avant, same year and mine was clearly lower by at least 5cm in the middle, their mechanics couldn't see it, and supposedly checked it and said it was all fine. Next time was on M4, just going along at about 70mph and it just fell off completely and exploded like a cartoon pigeon, thankfully no one behind us. Garage put on brand new one from Audi, £800. Next time it was our own driveway, a rock was on the ground, I measured it, its maximum dimension was 6cm, I took it to the dealership as they charged me £1100 to replace the whole thing and they said it was my fault and that any car that hit such a boulder would have been damaged. Within 6 months (mid 2022 now), the left side just started to hang lower and lower until one day it was dragging. I was 5miles from home so had no choice but to keep going slowly down the lanes, by the time I was home it was completely unattached, this time I got the local garage to have a go. They said they'd used extra bolts and washers and it was rock solid, and only charged me £75 as it took them just 30mins.

I just drove through a puddle, I got out and checked the puddle, it didn't go over the top of my trainers at any point, and the whole left side is off again. That's the fifth time.

So my question is: does anyone know a mechanic or garage who are genuinely ethical, who, if I give them more money, will actually spend a couple of hours REALLY checking the threads on the studs or nuts that it is held on with? Someone who - given that I'm willing to pay - will actually tap a new thread if needed, will actually use thread locker where appropriate, that kind of thing? Because there is no way that, having been driving for 25 years and having never had any kind of issue with the underside of any car I've owned (and embarrassingly large number), that the underside of this car could have fallen off 5 times without once actually hitting something significant... some fitting or other is clearly caput.

The other option is a ramp / pit that someone will hire me for a few hours, as I say, happy to pay. I just have a bit of a phobia of being under axel stands or jacks or even those little ramps. I think its a claustrophobia type thing, but I've never been great at trusting a car and being right under it.

Thanks for any recommendations. To be super specific, I live near Axminster, which is near Lyme Regis, about an hour from Exeter. Happy to drive quite a distance and happy to pay if someone actually knows someone who really, genuinely cares.