My research since original post confirms most of your information. A few questions:
1. What is source for Peter's imprisonment at York Castle?
2. What is source for idea that he may be son of John Loyall?
3. What is source for Sarah Kay's birthplace?
4. What's your interest in the Loyalls? (Mine is that Peter and Hannah are my wife's great-great-grandparents.)
I have considerable information on the family's Canadian and American life which I'm happy to share. Contact me at firstname.lastname@example.org