I'm by no means an expert in work visas and Doha immigration procedures but everything I have read and heard says that you cannot come back to Doha for two years to work because you don't have the NOC.  I don't believe your standing in Doha effects any of the other GCC countries or KSA.

But the best thing to do is ask an expert.  Call or email your embassy in the country you are interested in, including Qatar, and ask for clarification on your situation.

Best of luck.