There is no way to make the decision process faster. All you can do is ask about the status, or request GCMS notes.
I certainly DO NOT advise you to visit the embassy in Abu Dhabi, as I did this already and they don't allow anyone in. I saw people from Oman that came all the way to AD just to try and talk to anyone, and they weren't even allowed to enter. All you will see is a security guard and a closed door.
I tried everything, and I came to the conclusion that there is no way to make the process faster, you just have to wait. They sadly don't care if we miss our semesters or even our admission offers in some cases, they like to take their time in the process. I applied from Dubai for Fall 2016, and here I am joining late in Winter 2017 after missing my initial offer (got deferred), only because my visa took more than 23 weeks to get approved and stamped...
I really wish you hear from them soon, but there is no way to do anything other than waiting and sending the inquires that you mentioned...
When you reach the deadline for deferring, I think you should do it, rather than taking the risk and losing your whole offer -god forbid-
Best of luck