McCowns and MacAuleys?

Cousin Sam, who is descended from Eli, the younger brother of my great grandfather, William, just received his Y-DNA results at 25 and 37 of 67 markers. We match exactly at 12 and 25 markers and at 36/37 markers. The one marker value difference is on DYS 442 where he has a value of 13 and I have a value of 12. Of all of the Maguire related families descended from Donn Carrach Maguire, only one of two MacAuley lines has that same mutation at DYS 442. Now, we hope to learn if this mutation will help in finding our deep family history.