I understand your concern and it is well placed. The sources given here are; the grapevine, experience and known EK contracts placed on units in the areas mentioned.
Temporary accommodation is being used to make up for the lack of foresight of our clever MDs. There are just not enough villas in EKs price range and they have to wait for those that are to be finished. Pilots have had to threaten to resign before being moved.
These questions you have should be answered by Emirates themselves. The reason EK obviously have not and will not tell you where you will be placed is because they do not know themselves. They'll show you a clean and tidy house in a reasonable area when you are interviewed but once you've resigned from your current employer and moved here they know they can do what they want.
This is the reality behind the spin and your welcome to all things Emirates. I sincerely hope that you will be allocated a decent, clean and safe place to live for you and your family but quite frankly EK don't give a toss once they have you here as long as it doesn't cost them too much.