The only choice for the expeditionary Juan de Celada appears to be the individual who was a witness in 1537. If so, he was born sometime before 1507, making him over thirty when he went on the Expedition. This Juan knew the Estradas who were the in-laws of Vázquez de Coronado, giving more weight to the available historical record. Prior to the Expedition, he was a silversmith working in the royal mint. Although he served as a footman, he brought along an arquebus, which means he had more resources available to him than the average footman.
Porras Muñoz, El Gobierno de la Ciudad de México [p.116: 1526, a platero who was given the job by Alonso de Estrada along with Diego Martínez to mint money in the first Casa de Moneda in Mexico City]
AGI, Justicia, 191, N.6 [30 June 1537, Mexico City; witness knows Alonso de Estrada: Francisco Rodríguez, 30+, known the Estradas since they came, signed-no signature in copy; Juan de Celada, age-30+, has known the parties for 12 years in these places, signed-no signature in copy]
1540,Feb: Muster in Flint & Flint, Documents, Document 12 [Footman, arcabuz]
?Otte, Cartas Privadas, #46 [Mexico October 31, 1573, Juan de Cantoral to Juan Morán in Sevilla; Juan de Celada is his cousin from whom he received 2 letters]
?AGI, Indiferente General, 2057, N.101 [1576: Hernando de Palacios, confectioner, son of Juan de Celada and María de las Mercedes, with his wife, Ana Gómez, daughter of Juan Fernández and Francisca Gómez, with their children María, Francisca Gómez and Mateo, all vecinos of Sevilla; in order to be in the company of Juan Fernández, residente of Mexico]