James Finlay did go to the United States. He worked for an uncle in New York for awhile. Uncle unknown. He eventually ended up in Moscow, Cedar, Iowa. This is where he is buried. According to him he came to the US, and did not let his family know. He did not contact them for 50 years. His sister Margaret wrote back and told him, they thought he was dead. She told him about his parents and siblings. His parents and two brothers had already passed away. One brother married and moved to Scotland. This is where we got the names of his Parents and siblings. Also the death years of his parents. I have a copy of the letter.
John Finlay was born in 1817 and died 12 Dec 1877 in Annyart. Mary Ann was born in 1814 and died 6 Oct 1899 in Annyart.
According to Margaret and her husband William Hughes Census records, they were Presbyterian. Although I did see another Finlay family by them that said Church of Ireland. I believe they are recorded in the 1st Presbyterian records for Muckno Parish. But I can't get access to them to look. If you know somebody that could, that would be great.
I hope this answers your questions. And helps you out. My Finlay family from Ireland has been a mystery. Hopefully I'll get some more answers too!