I had a Octavia Mk2 with 1.8tsi BZB M6 and a Bluefin tune (and Golf R intercooler, round hard pipes, GFB DV+ and other bondage gear) and now have a factory stock 2017 1.8tsi gen 3 DSG Golf Alltrack. I'm not sure why you think it needs a tune to tow a lightweight camper trailer. The Alltrack feels more powerful than the Octy but I have been driving a 2.2 tonne Pajero Sport with 133kW/430Nm for 18 months and anything feels quick after that.
I am seriously in love with this Alltrack (in a purely platonic way).

Take the car back. Tell them you are totally unsatisfied with the tune and you want it removed and a full refund.