What if the Polish-Lithuanian Commonwealth wins the Polish-Muscovite War of 1609-1618? For reference:
What if the Polish King instead decides that there does not need to be a single religion throughout his entire realm and thus allows his son to acquire the Russian throne?
Sigismund's son, the Prince Władysław of Poland, was elected tsar by the Seven Boyars in September 1610, but Sigismund refused to allow his son to become the new tsar unless the Muscovites agreed to convert to Catholicism, with the pro-Polish boyars ending their support for the Polish–Lithuanian Commonwealth. In 1611, Kuzma Minin and Prince Dmitry Pozharsky formed a new army to launch a popular revolt against the Polish occupation. The Poles captured Smolensk in June 1611 but began to retreat after they were ousted from Moscow in September 1612.[8] Michael Romanov, the son of Patriarch Filaret of Moscow, was elected Tsar of Russia in 1613, beginning the Romanov dynasty and ending the Time of Troubles. With little military action between 1612 and 1617, the war finally ended in 1618 with the Truce of Deulino, which granted the Polish–Lithuanian Commonwealth certain territorial concessions but preserved Russia's independence.
What if the Polish King instead decides that there does not need to be a single religion throughout his entire realm and thus allows his son to acquire the Russian throne?