I purchased a part from them that required a $150 ...

I purchased a part from them that required a $150 core charge. I received that part and delivered it to my mechanic. The core was returned to me. It was not until I went to arrange a core charge refund that the return policy was presented to me. It stated that the core must be returned in its original box. Without it there would be no refund.
I contacted customer service (no human interaction available, only email) to explain to them that the box was damaged and disposed of by the mechanic. After several emails they put the fault on the manufacturer (Cardone) and that they would not accept the core without the box. I contacted Cardone, they have no such policy and they would accept the core from Rockauto without the original box.
After contacting RockAuto again to relay this information I was told that I was not going to get my core charge back and that all further emails would be ignored.
I stated to RockAuto that their core policy is NOT clearly stated until it is time to return it. And that the requirement to retain the original box should be clearly printed on the packing list in the box (where the core return "accept by date" is printed) of on the original box. This clearly seems to be a way to keep my money, $150 and not a requirement of the manufacturer. I will never do business with them and do not suggest anyone else do business with a company that is so unwilling to make an exception in a situation as this.