I've called the number many times for all sorts of different and sometimes complicated requests and never had a problem. Sometimes there were long holds while they were trying to check on things but that is pretty much my biggest "complaint." I've even had them undo my online check in when I was not going to make my flight due to delayed connection on a separate PNR, call Dubai control to complete this, and called me back to rebook me on the next days flight. In fact, they often ask for a number to call me back in case we get disconnected so you speak to the same agent without having to explain the situation anew to a different agent. To me, that's good service!

I don't think having an "accent" precludes anyone from proving good customer service nor has it been a barrier to comprehension on either my end or theirs.