I read your question and I understand your concern.
I don't think you have the same issue your mother had, that type of
artery narrowing your mother had surgery for is due to
atherosclerosis of the vessels and it does not manifest pain.
It would have been useful if you had said something more on the type of TIA you had, what manifestations in order to try and make a relation with the
neck pain. Also when did the neck pain begin, before or after. In theory it is possible to have neck pain with
stroke events in the case of dissection (a tear in the wall of the vessel) of neck vessels, but the neck should precede the symptoms normally not start 3 weeks later, so if that is the case it's not likely.
Anyway the
MRI will shed some more light, make sure to tell your doctor about the neck pain as well.
I hope to have been of help. If you could write again providing some more of those details on your symptoms I asked above I or my colleagues would be happy to try to give a more confident answer.