Hi IolaireNo experience in Montreal so far (we will be going there but not until next January). But in Canada, dialysis is done in hospitals only there's no such thing as a dialysis clinic. You'll need a good month of planning and every medical test in the book before someone will let you in.And you may have to be prepared to pay out the nose. My husband travelled once from Ontario to Saskatchewan (no charge for Canadians) but their info sheet said the price was $1,300 for non-Canadians for one four hour session.
$1,300 sounds like US prices, if I didn't have insurance it would be cheaper to fly to South Africa/America and get treatment there...
Just like to point out that Plattsburgh NY is about 15 to 20 miles south on route 15. Medicare would work there.
The Canada lab requirements are a pain, they require both a MERSA and VRE test.
https://www.cihi.ca/en/types-of-care/specialized-services/organ-replacements/e-directory-of-canadian-dialysis-centres-4Not sure if this is helpful. There may also be a separate private clinic for visitors (there is one in Toronto) but perhaps someone listed in this link knows more about what is available for you. Good luck and I hope you can sort it out.