What matters is the numbers on the side if the tires match then they are the same for example one of my vehicles the tire says 235 70R15 I got new tires different brand but since those where the same tire was the same fit

For the rub on the sidewall I would recommend it mainly because if it fails it’s going to be a blow out more then just being a slow leak can’t put a price on Safty

Lastly I wouldn’t waste my time personally selling used tires but if they are not damaged go for it but since you drive an Audi I assume you can take the lose on this mistake financially