Man, I feel for you. Makes me wonder if something wasn't done correctly on the second install. Dealer would normally reach out to Ford Engineering to get help on an issue as you described. Can't believe they would hand the car back over to you knowing the cranking problem....and admit that to you. Also, were the original catalytic converters replaced as well after the 1st failure? If they were badly damaged by all the extra oil, maybe they are plugged and/or damaged?
Have you tried contacting Ford directly about your experience? I think you would have a legit case for a buy back. Maybe engage a lawyer to see if it's worth pursuing? When you purchase a $70K plus car (CDN $$), it's not exactly chump change.
You might want to consider another dealer. Good luck and keep us posted on how things go.