Have you asked them how they audit/monitor their own performance? I think that's where I'd start.
Having had the misfortune to work in a call centre as an undergrad, my experience was that pretty much everything was measured and recorded. It's useful if you ever want to know how many standard deviations you are from the mean time taken to visit the bathroom, for example (wish I was joking), or whether it took you more or less time than expected from entering the building to signing in at your workstation. Obviously there is also a great deal of less facetious data tracked on call performance, resolution/success rates, random live monitoring of calls etc, much of which is captured automatically.
It might provide some ideas as to where to start, and with your more general auditing experience you may spot some gaps or areas where they can improve their own monitoring and do more of your work for you, whilst improving themselves.