Could an 11th-century contract prove the existence of same-sex marriage in medieval Spain?

In 1061, two men, Pedro Díaz and Munio Vandilaz, signed a legal agreement in which they undertook to share the management of the house and church of Santa María de Ordes—most likely the current parish of the same name in the Ourense municipality of Rairiz de Veiga, in Northwestern Spain. Judging by their surnames, the men were not relatives but rather, as we will see, friends.