During the end of 15th Century the Tondo Dynasty was replaced by a cadet Bolkiah after Gambang was defeated, perhaps a scion of the Tondo Dynasty could ask help from the Japanese since I think there are still surviving descendants of this royal family but they are now unknown, in OTL Lakandula asked the Spanish for help against Sulayman but accepting the Spanish vassalage which sold the Island was a treacherous move.In fact, that could very well be the POD that enables Oda Nobunaga to unify Japan, and go on to reward Daimyo with territory in places such as the Ryukyu Islands, Taiwan and Ezo and then maybe Tondo before the Spanish even get there. If the Spanish can conquer Lapu-Lapu, Oda Nobunaga surely can.
But moving a finger with Tondo will surely cause a war with Brunei..