MRIN is a numbering system for individuals used in some genealogical software.

I'm confused. Are you saying that there were two Dan Teares of Ballacunner who married two Mary Cormoads, in different generations?
It looks like a typical internet mix-up, where someone has (mis)copied someone else and been copied by others, perpetuating garbled information - but of course I could be wrong. You need to use original records (or films/scans of these), and ignore anything without clear sources, which you then check for yourself.

Sue