Yeah definitely get the oil and filter changed, by someone who has done it before
Make sure whoever sources the parts gets a genuine filter from Audi or TPS and supplies the VIN as there are two versions of the filter.
Several of the problem areas in these gearboxes are lubrication-related so clean fresh oil will definitely prolong its life. The myth about changing oil dislodging deposits is precisely that IMO - these gearboxes are normally spotless inside.