Dave
I have raised this same questions with my Lawyers in Manila and will let you know what I hear back. They are aware that even with all the papers some girls dont get out miss flights etc.
Now they have not said what visa these people had but I am under the impression a visit and settlement visa should and would be viewed totally different.
You're not alone being paranoid mate - I am too but I'm still stuck on waiting for a TOEIC pass for the speaking test!
According to the post you mention a letter from you stating you are covering all costs when you land is all that is needed.
I am potentially going to fly to Manila and bring my Mahal back after a couple of nights in Manila partying! Lets see..
Tone