Same promo, same problem.
My own visa card, I'm the sole passenger. Booked while in Dubai, maybe this flagged them. Sent the passport, didn't bother with CC statement. Got an email:
"Thank you for contacting Qatar Airways support desk, In order to complete the verification, please provide the bank statement of the card used to book the reservation, kindly note that in absence of bank statement you may also provide the snap shot of the statement downloaded from online banking which shows the charge from Qatar Airways and the last four digits of the card."
Sent a snapshot of my online banking page for the transactions on that card, mentioned that I can present the card at check-in and that the whole verification idea is nonsense (in kinder words)
. Let's just wait and see.