Mihai, who was also recognized as a Cup-bearer, stated a claim to his share of the Coiani inheritance, demanding in particular 4,000 Goldgulden pledged by the Empire to his maternal grandmother, Elena Șerban. He was still attached to Vienna, with Ferdinand III forcefully keeping him on his entourage and considering him for the throne of Transylvania. In 1643, he was trying to instigate a pro-Habsburg rebellion among the Romanians of Transylvania. This prevented Prince Matei, whose sons Matei II and Mateiaș had both died, from adopting Michael the Great's grandson. In 1654, formally released from Austrian service, Mihai made a final effort to regain Wallachia, counting on assistance from the Cossack rebels. He fell ill with the plague upon reaching Bohdan Khmelnytsky's court in Chyhyryn, and was recorded as dead by 1656. One tradition suggests that he was the suitor for Domnița Ruxandra, daughter of Moldavian Prince Vasile Lupu and widow of Tymofiy Khmelnytsky. Some scholars also argue that he is the "Michael Vaivoda" depicted in a 1651 engraving by Elias Wiedemann.