I don't think anyone outside the Philippines still take him seriously. As for the containers unless he can find a connection between that private company and the Canadian government, he really can't force Canada to do something about it. The Philippines just don't have leverage in anything.
He can claim a connection of course (like how almost everyone believe the CCP give orders to Chinese companies operating outside China) but he need to find a way to sue them.
I don't remember if they've already went after the local company that's supposed to "buy" the "recyclable" materials.
Yeah if the canadian government claims these are from private companies, it's going to be difficult dealing with it legally unless the philippine government can exactly pinpoint where it came from. With the ph president's overfriendliness with china, it's also not going to get him much attention from western countries. Going to war against canada over garbage is a big joke and this president knows it.