The dialect is strange - google seems to analyse it as Corsican rather than Italian (but indeed, Corsican may well be closer to the archaic Italian dialect than modern Italian!?), and translates 'triunfi' as cuturnu (Lit, a woman with horns, figurative a cuckhold, a man married to an unfaithful wife).*
"triunfi" instead "trionfi" is very much used in the Esch paper (related to the custom register in Rome), it seems to be common in the language of the custom officers (in Rome). And the import is rare, it's for the officer a word, that they spell different:
One importing merchant: 7x triunfi, 2x trunfi, 2x trumfi
Another: 5x triunfi, 1 trunfi, 1x trumfi
but also "triumphi, treunfi, treumfi, triomfi, trionfi, trumpfi, trionphi, triomphi, trumfi" (all these more rare)
triunfi is definitely the winner in the spelling race (in Rome), roughly counted 55x triunfi of 107 (so a little more than 50%), 1x trionfi of 107
Pico in his wiki biography ...
Soon after this stay in Florence, Pico was travelling on his way to Rome where he intended to publish his 900 Theses and prepare for a "congress" of scholars from all over Europe to debate them. Stopping in Arezzo he became embroiled in a love affair with the wife of one of Lorenzo de' Medici's cousins. It almost cost him his life. Giovanni attempted to run off with the woman, but he was caught, wounded and thrown into prison by her husband. He was released only upon the intervention of Lorenzo himself. The incident is wholly representative of Pico's often audacious temperament and of the loyalty and affection he nevertheless could inspire.
Pico spent several months in Perugia and nearby Fratta, recovering from his injuries. It was there, as he wrote to Ficino, that "divine Providence ... caused certain books to fall into my hands. They are Chaldean books ... of Esdras, of Zoroaster and of Melchior, oracles of the magi, which contain a brief and dry interpretation of Chaldean philosophy, but full of mystery." It was also in Perugia that Pico was introduced to the mystical Hebrew Kabbalah, which fascinated him, as did the late classical Hermetic writers, such as Hermes Trismegistus.
It looks, that Pico wasn't often close to Rome. I don't know much of his life. The love affair was May 1486 and then (after this) he wrote his 900 theses (so he can't have intended to publish them in Rome before) in a state of writer ecstasy, half crazy (so says my memory of that, what I read, but this wasn't much).
Perhaps the "triunfi" in the poem tells, that he wrote this 1486? Naturally not as a sure evidence ...