Peggy Smith confirmed her connection to this family line and sent details of son James’ marriages to twin sisters:

“My great grandfather was James Mutch born Cruden, Aberdeenshire c.1859. He married first Mary Balfour then, after Mary’s death, he married her twin sister Margaret. James died in Dundee 1887”

Based on this information I found the marriage records for both sisters and Mary’s death record in Scotlands People.

Thank you Peggy, and (yet again) apologies for mislaying your original email