RB101

Hello all, new poster here. I’ve had my 2017 audi A3 2.0 diesel for nearly 7 years, and been a great reliable car. However I noticed a coolant leak in December, my regular garage could not find a leak but they said they saw coolant staying at the bottom pulley and suspected leak or weep from water pump. Advised I monitor for a couple of weeks and come back if still leaking which it was. They recommend replacement of the water pump and timing belt which has been done but the leak is still ongoing. Doesn’t anyone have suggestions as to what else could be causing the leak? I’ve spent nearly £1k on this issue so keen to narrow down possibly causes without endless trips and costs taking back to the garage. thanks in advance. Rob