PostNet Wonderboom Junction refuses liability after staff's negligent packaging ruins R1,200 sale

I took an artwork piece to PostNet Wonderboom Junction to be shipped. The store consultant, Geraldene, wrapped the item herself in bubble wrap, marked it FRAGILE, and explicitly assured me it was fully secured for transport. The item arrived damaged in transit with new cuts and scratches, causing the buyer to cancel the order. When the claim was submitted, Aramex rejected it, citing "insufficient packaging." Despite their own staff member packaging the item and guaranteeing its safety, PostNet Wonderboom Junction is now washing their hands of the matter and shifting all blame to Aramex, leaving me R1,200 out of pocket. If a customer relies on PostNet staff to package an item and the carrier rejects a claim because PostNet's packaging was inadequate, the responsibility lies squarely with PostNet. Appalling lack of accountability and customer care from the Wonderboom Junction branch.