Damaged Lenovo S130 in a sealed box from Makro.

I bought two Lenovo S130 from Makro PE on 11 Feb 2019. Upon opening the boxes at home, I discovered that the one laptop had a small crack on one of the corners. When I returned it to Makro PE earlier today (12 Feb 2019), I was given an interrogation as to the condition of the box, which had no visible damage. The store salesman, his superior, as well as the store manager doubted my version that I received a defective item from a sealed box, but they could also not guarentee that the item was not indeed broken in transit to their stores, because the salesman did not open the boxes in store to check. Item manufacturing date on the box shows 18/11/14. Does this mean it was manufactured in 2014?

The store manager insisted that they have to send it to the manufacturer for assessment, but could not tell me how long I have to wait. What assessment exactly he could not tell me, because clearly the device has a crack in it. Will they blame the customer?

My question is why should I as a customer be negatively affected by this defective item that Makro sold me. I expect that all items in a sealed box will be new and without any damage. If Makro want to blame the customer and make us wait, then they should as a principle open all boxes infront of the customer.