I use Cheapoair. I've never seen a hidden carrier ticket, but I only use them in Asia on airlines that don't have English websites and such.
If you book on Cheapoair, you'll get two charges on your CC. One is for Cheapoair service charges, the other is for the airline directly. So you get the 5x MR's on an AMEX pers plat.
Again though, I've never used them for a hidden carrier ticket, so I cannot vouch how that will post to your CC's.