Foreigners kidnapped from Samal resort in the Philippines

Today was a reminder kidnapping is still going on in the Philippines. But what puzzles me is why the kidnappers came to Samal. Its a long route back to safety for the kidnappers, but also was anyone a high value target or was this more to do with the presidential election and the Mayor of Davao Rodrigo Duterte. The reason being although Rodrigo Duterte is not running for president currently he is a very popular individual creating Davao as one of the safest places on the planet. This kidnapping right off his shore may be more to do with why the kidnapping happened than the people kidnapped.