In 1317, Nicholas Atyinai (from the gens Aba) donated the estate Konchyan in Slavonia to the brothers, because they played a significant role in the release of him from the captivity of John Kőszegi.
[1] When Ladislaus Kán was reluctant to recognize the rule of Charles, whose claim had been supported by the Catholic Church, Pope Clement V ordered his excommunication in October 1306, but Peter Monoszló disagreed with that step and expressed his displeasure.
Sălăgean argued that the tangible cooperative relationship between Peter Monoszló and Ladislaus Kán in this period was influenced by John, who managed the diocese's affairs as the confidant of the oligarch.
John handed in the appeal of Peter to the Dominican prior in Gyulafehérvár; he probably acted on his own, still, his influence on the bishop appears to be decisive as of that moment, as Sălăgean claimed.
Sălăgean considered that John plausibly obtained preliminary approval from the canons with respect to his designation as the next bishop of Transylvania, succeeding Peter Monoszló, whose health had deteriorated significantly by then.
[3] According to Tudor Sălăgean this step prompted John to fled the oligarch's allegiance and swore loyalty to Charles I, who by then remained the sole monarch in Hungary.
[3] In contrast to Sălăgean's theory, Hungarian historian Sándor Hunyadi rejected that John would have been the voivode's loyal man at any time, since the chapter would not have tolerated Ladislaus Kán taking control of the diocese through his confidant.
[6] On 17 August 1309, majority of the canons elected Benedict, initially Ladislaus Kán's confidant, as the bishop of Transylvania, but John Bogátradvány protested against the election to the judicial court of papal legate Gentile Portino da Montefiore in late August 1309,[10] which resulted launching a second lawsuit on 1 September 1309 with the mandates of Filip de Sardinea and Johannes de Aretio.
Pope John XXII appointed him, alongside Augustin Kažotić, Bishop of Zagreb and Nicholas III, Abbot of Pannonhalma, as conservator (guardian) of the Archdiocese of Esztergom and its metropolitan Boleslaus in December 1321.