Just be aware that your terms do not supercede legal realities. I see dump trucks with signs that state that vehicles must not follow closer than 200 feet and that they are not responsible for broken windshields. However, you have to get closer than 200 feet to read the sign. I asked my father (the retired DA Investigator) about this many years ago and he just laughed. That's when he told me that, just because someone makes a statement does not make that statement true and it certainly doesn't make it legal. To be fair, what I quoted you above wasn't so much about legality or regulations. It was based more on Paypal demands and practices. I assume that they paid you using either PayPal or Stripe. Stripe is even stricter than PayPal when it comes to pleasing the customer first.
I don't say the above to be argumentative. But I have been selling items at least part-time for 15+ years and I am now in my 11th year as a BrickLink seller, 9 of those years as a full-time seller. I have a perfect record. I have never lost a PayPal or Stripe case as a buyer or seller, not that there have been that many. Not to be an ass but, once your buyer offered to pay outside of BrickLink, he became a thief in my eyes, not to be trusted. I would have immediately cancelled his order, listing the exact reason(s) in the comments. And then added him to my Stop List. Doing so would have saved you from this type of crap.