There is always a risk when it comes to using a foreign credit card. I just had a Avianca booking charged 2 months ago post only recently when it was the exchange rate at the time of post that was used. I paid nearly $100 more than what would have been 2 months ago. I called my bank which issued the card and they said they had no control and couldn't care less.

So in the OP's case, even if the hotel charged the card instantly, there would always be a chance like what I experienced happening.