Qatar Airways unfair refusal to reimburse ticket

We are very disappointed with the customer service from Qatar Airways and we will never be flying with them nor recommending them ever again. On our journey from Barcelona to Doha, our plane arrived in Doha at 05.30 in the morning and we needed to catch a connecting flight to Johannesburg at 06.20. Although 50 minutes to catch the connecting flight appeared to be enough time, we were unable to catch the connecting flight due to the extremely slow baggage control process and the very far distance to the boarding gate (E22) which delayed us significantly. Even though we rushed to the assigned gate after standing in the very long baggage control queues, this was still not enough time to get to our departure gate in time. We feel that we should have received assistance from the airline to allow us to jump ahead in the queue, especially since the time of our flight was then scheduled to be 20 minutes earlier. We were required to buy new tickets to Johannesburg (U$S 1881.44), and the airline has refused to reimburse us for these. I am convinced that if we had assistance from Qatar Airways, and if our flight QR1363 had not been brought forward 20 minutes, we would not have had this issue.