Has the transaction actually posted, or is it still Pending?
Yes. it posted as "AMEX FINE HOTELS AND RESORTS". It also didn't trigger an email from Amex letting me know the Hilton offer was met. This is the only FHR booking I've done so far this year. So unsure if it is specific to Hilton or double dipping will no longer be possible with Amex offers for other properties.