Rotten products, no assistance and store manager has a bad attitude

I bought hampers at Eskort Princess Crossing on 01 September 2017 and find out that 2 of french polonies are rotten but the expiring date is 2018. I went to the store to find out what can be done about the situation, one of the staff members advice me to bring it back with the till slip for exchange. I brought it back on Wednesday 20 September 2017 and she took it to the store manager by the name of Neil Van Der Merwe and he told me he won't exchange it for me because it's opened. When I asked him how was the customer supposed to know that its rotten without opening it, he couldn't answer. I then asked what is gonna happen if I come across the same problem, he said he will change it then. He had a very bad attitude, he even told me to do what ever I want about the complaint. So what I want to understand is that, since this is a sensitive issue as it can cause illness to customers, what does Eskort do with problems like this? Is the kind of service they promote in their stores since the bad service came from the store manager? This is a serious matter that needs to be resolve so that it doesn't happen in future as it can cause illness to customers.