Gallo returned to Santiago del Estero and was a signatory of the peace treaty of Vinará in 1821, signing on his province's behalf with Pedro Miguel Aráoz of Tucumán and José Andrés Pacheco de Melo of Córdoba.
After returning to Santiago del Estero, Gallo participated in the signing of the peace treaty of Vinará in 1821, representing his province alongside Pedro Miguel Aráoz from Tucumán and José Andrés Pacheco de Melo from Córdoba.