Coolant leak

[H-M3]

Hi peeps hope everyone is keeping safe.
Recently my D4 has started to lose coolant, as I am driving very little I didn’t realise until 2 weeks or so when the coolant light came up. I topped up few weeks back and this time it has dropped to min at the reservoir. Also you an smell slight coolant burning smell. Under bonnet you can see water near the pulleys on the right side standing from the front. I spoke to a indi Audi specialist who is confident that it’s likely to be the Water pump as they are common failure on the 3.0tdi? Now the other issue I have is, yesterday I turned the AC on and it worked fine no issues. Today however I checked under the bonnet and I can see the serpentine belt was shredding on the edge nearest to the engine! There were bits on the engine guard. Now this has got me worried. Do you think it could be the AC pulley? Mileage is 89k so is this stuff wear n tear? I had to drop off to garage today so let’s see what they pick up.