A Christian Bruneian Empire under Agustin de Legaspi

Agustin de Legazpi is a prominent historical figure in the Philippines best known as the leader of the Tondo Conspiracy of 1587–1588, the last native ruler of Tondo, and the last individual to hold the title of paramount ruler in any of the Indianized indigenous Tagalog polities of the Pasig River delta,[1][2] although it had been reduced to little more than a courtesy title by the time of Agustin de Legazpi's execution.[citation needed]

From what I have heard he is married to Putri of Brunei, he can take over Brunei himself if he succeeded against the Spaniards.
How would a Christian Brunei look like and would they ally with Portugal and the Dutch.