The days go by and negotiations in Guisando do not come to fruition. As Chacón and Cárdenas feared, Enrique's good words do not become facts. Pacheco helps to delay negotiations until the exhaustion of those present and the papal legate, Veneris, arbitrator of them. Meanwhile, the Mendoza have made public their defense of the rights of the daughter of the king, rights for which they swore solemnly. Contrary to the negotiations with Isabel and fed up with the king's swings, they even threaten to denounce their dealings with Rome. Isabel and his people, surprised that the Mendoza do not support, as is tradition in them, the king, decide to find out what happens and discover the pregnancy of the queen with a lover, which increases the doubts of Enrique's fatherhood.