If the hotel wants your business...
American Express is up front about the coding issue in their account terms and realistically can't police every transaction to make sure the merchant coded it properly. So that leaves it up to you and I don't think even if you found the right person, anyone at American Express can ethically change the coding as coding is up to the merchant.
I too have had this problem with both my Costco Amex and my Citi Platinum Dividend cards. So, here is what I do - I make it known to the merchant that if they want my business or future business, they need to code the transaction properly (and I mean it). You need to contact the merchant and if they don't fix it immediately, then you need to work your way up the chain of command with the merchant.
Good Luck!