Should timing belt get replaced when thermostat gets replaced? on 2001 Audi A4 Quattro

My MIL came on and after taking it to a certified Audi mechanic, I was told that the timing belt should also get replaced, since practically the entire engine needs to be taken out. I had the timing belt last replaced in June 2007 and have since put 21,000 miles on the car. I currently drive less than 5,000 miles per year. Should I still replace the timing belt at the same time as the thermostat or can the old timing belt be put back on?

Asked by for the 2001 Audi A4 Quattro
You may not need the timing belt right now. But if they are removing it already for other repairs, they should put a new one on for just the cost of the part. This is good because It will save you hundreds of dollars should you need one in the near future.
Thank you for your prompt reply.