American Express Membership Rewards - Obligated to also pay using Amex Plat after booking FHR?

I realize that you must use PTS and your Plat Amex to reserve an FHR property, but once you check in, are you also obligated to pay with the plat card? Has anyone tried paying with a non-plat amex after booking an FHR with PTS?

You are specificly allow to pay with any ANY Amex card product that you choose.

This is clearly stated in the terms and conditions.

But, you are suppose to pay with Amex., not Mastercard , Visa or cash.
other posters have reported diffuculty, aruguments when trying that.

Ah yes, thank you. For some reason I didn't catch that in the T&Cs.

I've gone back and re-read it and it is quite clear. Cheers.

Having checked in with a Centurion, I've often paid with Mastercard. Most hotels don't mind.