Thank you very much William. Yes, you understand the situation exactly right. It's hard to know what information you can really get from the offshore call center, but the impression I got was that there are some Hilton hotels on a "no use" list for the gift cards, and they said to try at a different hotel and maybe I'll get lucky that time. I did at one time ask for a supervisor there, and after the obligatory "They'll just tell you the same thing", I got put on hold and gave up after an hour.
If you can approach Amex from a partner standpoint, that would be the best result I can hope for. Here are some questions I asked in my email:
1. How is presenting a Hilton gift card at a Hilton hotel a fraud concern, and what exactly does Amex want to see for it not to be?
2. Are the 2 hotels I visited really on a "no use" list for gift cards? How many such hotels are there, and can we know what they are?
3. In the same way we can do that with our regular credit cards, could someone from the hotel have called Amex to clear the fraud alert?
4. Will Amex do anything for people who unexpectedly had to pay out of pocket at checkout (for example, debit the gift card and mail a check) ?