Withdrawal of Accepted Paper So, I think that I'm in quite a mess here.
I recently submitted a paper to an IEEE conference and got my paper accepted. I submitted the camera-ready paper and the copyright form but weeks later, after the submission, I found out that all the authors including me were assigned the job of conducting exams for undergraduate students and as of such we were not allowed to decline. So I sent a withdrawal request to the conference organisers and got a reply today saying that our paper was removed from their 'list'. We had already registered the paper in the conference as well.

Now, since we had already submitted the copyright form but the work was yet to be presented in the conference and published in IEEE Xplore , is it possible for us to submit the same paper in another conference knowing that the paper has been removed from the list?
I would write in to the conference, explaining your situation and that this is - as you far as you are concerned - a case of force majeure. 

First, you could ask for the registration payment back if they still decide not to publish it (not many chances you'll get it, but if you ask in a professional and nonagressive way, who knows). 

Second, you confirm with them (in writing) that your understanding is that this means the paper is now free and can be resubmitted elsewhere (i.e. a confirmation that the copyright transfer is void under the given circumstances). 

They cannot get the money,  remove the paper from the proceedings and also expect you not to submit it somewhere else.