You cannot send the SDK to anyone. You cannot even send the Mathworks header files (though the wording in that part of the license makes my head spin, so I might have missed a loophole.) You need to look at the Terms & Conditions and read about Generated and Derived and some other cases. It is difficult text to understand all the ramifications of.
When I was looking at the T&C recently, before my mind forced me downstairs to eat some ice-cream, I was getting the impression that what you are permitted to send people or make public any code you wrote yourself, and you are permitted to send people or make public the executables (but it might only be "send"), and you are permitted to send MCR (but definitely not "make public", there are Rulez!).
But sending generated source was a No-No, and sending generated source that you had hand-edited was a Huge No-No, but then it seems to get into rules that you have to follow if you are not going to follow the rules.
Sending header files (that you had no written yourself) was Specifically Prohibited.
So you can't send the SDK. If your customers want the SDK then they have to buy it themselves, and then whether there is an ITAR issue is up to Mathworks to solve in determining whether to sell to them.
Warning: I was not under the influence of sufficient chocolate when I was reading the T&C this last week. I probably got some details wrong. Read it yourself. Have your lawyer read it yourself for you.
