Hello Jackie,
Many thanks for being in touch with the forum.
It is highly unlikely that the issue of the car not sitting correctly is as a result of a shock absorber failure. The most likely cause would be a broken spring - which is not at all uncommon.
If this proves to be correct, then this raises the question about the whether it is wise to also renew the spring on the opposite side at the same time. In my opinion, yes, it is,
Now the other question is - why are you arranging for any repairs on this 5 year of car to be undertaken by a main dealer? Logic points to asking this question, when you were prepared to take ownership of the car without even checking that the VAG dealer it was bought off, had serviced it before sale to you. If you couple these questions, with knowledge that an Audi main dealer labour rate is likely to be north of £100/hr plus VAT - £120/hr. may result in you considering getting this car serviced and repaired at a trusted local garage.
Since you have the main dealer cambelt cost, you can now easily obtain local garage costs - using Audi parts, which you can buy mail order at discount ( I would be able to suggest a couple of sources if (in caps) you are serious about embarking on this alternative route.
Main dealer cost to renew a spring - and/or shock absorber can easily be obtained in advance from the dealer where the car is booked in to.
Hope some of this helps to address a sensible resolution to your issues.
Kind regards,
Gareth.