Product used twice and now useless. No refund or exchange allowed

I am writing on behalf of a pensioner who I stay with. This lady purchased a verimark vacuum cleaner at Builders Warehouse on the 4th of April 2018. At the time of purchase she was told to bring the machine back for if there were ANY issues. No separate Verimark exchange/return policy was provide and she left with the Builders Warehouse slip that contains their returns policy. Can be viewed online: https://www.builders.co.za/refunds-and-returns. The machine was only used twice and the extension arm tubes split down from the rim where the other tube fits in. This is a design flaw as the tubes do not fit into each other very deeply and the plastic is so thin and brittle that any amount of pressure (normal of pushing a vacuum through carpet), would cause the plastic to crack and split. Yesterday I went with her to return the item. All original packaging - plastic wrapping, packings etc. was returned with the invoice. She was first told by Verimark that they have a separate returns policy of 14 days - we asked to see where this made known to us, to which they couldn't provide us with. They then also said that the warranty only covers the motor and not parts and they cannot exchange parts either. To add insult to injury they then imp**** that we had either forces the pipes together to forcefully or app**** to much pressure while vacuuming, explaining that even though the vacuum is extremely powerful it should not be used at such a strong setting. Well then what is the point? And why are these instructions, together with the terrible returns policy not provided at time of purchase? Another lady came in while we were there and also said she had terrible service from Verimaak and would purchase from them again. The manager at Builders Warehouse said it was not their problem and we had to take it up with verimaak themselves - even though they sold us the product. It should be their problem and not the problem of an elderly lady. I am also disgusted with Builders - but that we will deal with separately. She does not want an exchange as this is a design flaw and will happen again with new extension tubes (pipes). She would like a refund so she can purchase a different product. I will also take this up with the CPA in terms of not having first been notified of the policy and limits on the warranty.