Even as an extremely loyal customer, I have experienced the same sort of thing several times. Sadly, their Customer Service or Complaints section / division / office / department / man, is abysmal at follow ups and it is one sad failing in a company that has so much else positive in terms of customer service.
If you have a problem like yours indicated above, don't expect a speedy response at all from QR, unless you telephone their headquarters and demand to speak to their CEO. He, in actual fact, WILL take your call at some point and he WILL get to the bottom of it, if you indicate that you have a serious complaint.
Sadly, the fact that you have published the names and numbers of the perceived "culprits" here will mean that you will be asssured of a very speedy response now tomorrow, followed by the likely termination of the people who's names you mentioned!! Just remember that if you are indeed a non resident or expat resident, Ramadan and IFTAR is an important time, so cut that particular guy a little bit of slack. This is the Middle East.
Welcome to Al Qataria.