No, the 2 pax were not able to present the cc used for payment for the tickets and were thus denyed check-in. This is common for Asian, including Thai carriers, that you need to show the credit card used for tickets purchased from the carrier's webpage in order to prevent cc fraud. Please note that this does not apply to tickets purchased online from 3rd party, including travel agents/OTAs.

Most likely your attention was drawn to this when you booked the tickets online and you should have acted accordingly (sorry, but I have to point out that you could have avoided this situation if you had noted the cc requirements)