Was the DSG serviced at all before that mileage? They should be serviced every 38,000 miles religiously!! Earlier is fine, but later is no good, even at 38,000 miles some gearboxes act funny towards the end before they get serviced and fresh fluids put in.
I also change the fluid every 4 years if the mileage has not come up by that point, even though Audi only specify a mileage limit on the oil, not an age limit, it's cheap insurance to do it sooner, as oil will degrade over time, not just by mileage.
I would be VERY sceptical of touching a DSG box that has not been properly maintained, especially the ones before 2012 which suffered more issues than the later ones.
In terms of missing 1 service affecting resale value or causing other issues, I wouldn't be bothered, as engines are usually very good and can handle 1 missed service, and buyers usually don't mind if 1 stamp is missing.
Also, how long was the time frame between the 33k & 52k service? If it is on a Long Life Service Plan then Audi state the oil should be done every 2 years or 18,000 miles....in which case if it was done after say 18 months and 19,000 miles it has not actually missed a service, but rather had a service just 1,000 miles later than it should have done! So it may well have a FSH.
However the lack of DSG maintenance concerns me more than anything to be honest. By now I would have serviced the gearbox twice if it was my own car (8 years old, despite the mileage) and Audi say it should have been done 15,000 miles before they actually did it!
