Robert is certainly right that Mindanao looks to be the best place in the Philippines for a spaceport based strictly on geographic considerations – presumably somewhere along the island’s east coast. I note that the block quote in Robert’s post mentions one of the involved parties as being the Cagayan Economic Zone Authority (CEZA). And there is a city on Mindanao named Cagayan de Oro. But this city is located on the northwest shore of Mindanao and is, in any case, not the Cagayan of the entity referenced in the block quote. The CEZA entity controls the Cagayan Special Economic Zone and Free Port (CSEZFP) which has an area of 54,000 hectares. But it is located on the western side of a peninsula that sticks out of the northeastern part of Luzon, not Mindanao. The province of which this peninsula is a part is called Cagayan. The peninsula has an east-facing coastline but I don’t know if the CSEZFP extends far enough east to include any of it. The CSEZFP, itself, apparently sits somewhere between the municipalities of Gonzaga and Santa Ana – I couldn’t find a map that shows its exact location or boundaries.

Perhaps, even with this less-than-ideal-seeming location, the CSEZFP has little or no population to its east – which could make overflights by rockets acceptable. Or, if not, then someone is going to get risk getting bowbed if rockets start flying overhead – especially rockets early in their development/operations histories. Perhaps it’s always bowb your buddy day in the Philippines as well as in the Mobile Infantry (Harry Harrison’s Mobile Infantry, that is, not Heinlein’s).

Anent Mindanao, the Bangsamoro Autonomous Region in Muslim Mindanao (BARMM) is a recent replacement for the previous Autonomous Region in Muslim Mindanao. It’s really still in the very early days of being a thing. It includes a decent chunk of southwestern Mindanao as well as most or all of several much smaller islands to the west of Mindanao. The BARMM seems to have about the same relationship to the rest of the Philippines as Scotland does to the rest of the UK – a separate British-style parliament, for example. BARMM-y. :)

None of BARMM’s territory seems well-suited for spaceport use. If anyone built a spaceport on a suitable piece of Mindanaoan real estate – eastward facing – I imagine the Muslims would be quickly sniffing around after a “fair share” of the jobs involved and perhaps making additional demands.

If one did not wish to build a spaceport quite so far north as northern Luzon but also wished to avoid Muslim complications on Mindanao, a good split-the-difference location would seem to be Samar – though I have no idea what the state of infrastructure is there.

I wouldn’t even risk an Estes pad

Obviously that is a separate question from whatever shore based spaceport the Phillipine government may be thinking about establishing.