It is true that it is easier to find vegan options in some places (like New York where you can devour all the vegan donuts you want) and less so in others (like Cagayan de Oro where I have just been). Since the Philippines is made up of 7,107 islands, every time I travel locally, the question of being on an island becomes quite real, though it is a choice and I am far from stuck on it.
In Cagayan de Oro, there is one vegetarian restaurant called Green Haven. These are what I had to eat: vegan versions of liempo and mongolian lamb. It's so-so, and a bit expensive for the portion and quality, but one cannot say there is NOTHING to eat. Just check out the menu.
And if you still want to ask me what I would do if I were truly stuck on a desert island, just check out this podcast episode by Colleen Patrick-Goudreau.
Please go vegan and spare 100 lives a year from senseless slaughter.
Peace and love to you!