 He eventually regained the royal favour and was sent as ambassador to Rome.While there, Bouillon employed the sculptor Pierre Le Gros to carve the main components of the tomb he planned to erect for his parents at the Abbey of Cluny (the sculptures were finished by 1707 and arrived at Cluny in 1709).Contrary to the wishes of his king, he championed the cause of Fénelon against that of Bossuet and did all he could to prevent the condemnation of Fénelon's "Explication des maximes des Saints".