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Unfortunately, the RC records for Ballintemple parish start in 1862 so no baptismal record would be available for Owen and I did not see a marriage record. The spelling of the townland where they lived would be Corduff. I looked at the 1855 Griffiths Valuation head of household listing and there were seven McCann records and there was John McCann in Corr. I'm wondering if that was shorthand for Corduff https://www.failteromhat.com/griffiths/cavan/ballintemple.htm
Do you know if Owen had any siblings? I ask because I searched the subscription site Roots Ireland for Ballintemple records 1862 on and found a John McCann/Mary Lee couple who lived in Corduff and had the following children: Patt 1865 John 1868 Mary1871 Thomas 1873 Anne 1880 Below is a link to the birth record for John (5th record on page)
Let me know if you see a possible connection.