Join Date: Apr 2009
Location: Bye Delta
Programs: AA EXP, UA Silver, HH Diamond, IHG Plat, Hyatt Plat, Marriott Titanium, Nat'l EE, Avis PC, Hertz PC
Posts: 16,633
+1 on if Amex can't see the transactions, they didn't decline them.
Never knew this until a few weeks ago, but you can also see recently declined charges online if you go to Account Service --> Credit Management --> Recently Declined Charges... it lists the reason for decline.
And I've never had anything short of great customer service with Amex... can't say the same regarding Chase...