There can always be exceptions to what is normal. But in this case you are clearly talking about some American who is in the top 0.1% financially and there is even less than 0.01% chance of any American expat in Vietnam being in the top 0.1% of Americans financially. Even that 0.01% figure is high when one carefully considers the real estate ownership & visa/residency laws in VN and the alternatives globally. Its probably more like 0.004% chance or 1 in 25,000 single Americans in VN.
100 million VND is approx 4400 USD per month which is about what an American earning $600,000 per year would have to pay for child support in the USA on 2 children, assuming he doesn't have any other minor children or stepchildren.
How does an International School factor in for FAPE? It doesn't so its nearly impossible to suppose that any Child Support order that could be made or enforced in the USA would include any such allowance. If someone doesn't know much about FAPE then they really can't get into this topic. Wherever Dad lives in America the Courts have Judges who have to go before the voters for election/retention and for a Judge to suppose that their local schools aren't as good as the ones in Vietnam would be political suicide. And same goes for servants and many other things that people can dream of being "necessary".
Its always possible that the parties themselves could work out some agreement that covers these things and maybe more. If the parents agree that a child must have a 100 karat diamond ring for every finger, lots of private jets for family outings, 35000m2 Beach house, 40000m2 mountain house, best penthouse in HCMC, and other things then I suppose they can do this. There is no limit to what the human brain can imagine. Good luck getting that done if the dad works for some English center that has been closed for 6 months and even when it's open they go months without paying him.
The reality is that almost all expat Americans living in VN right now have a lot of financial troubles and that its not realistic for those having children with them to dream like gold diggers.
100 million VND per month for 18 years is 21.6 billion VND. That is over 950,000 USD and nearly a million bucks. Most Americans don't even have 400 USD saved up to pay for emergencies. If there are any gold diggers reading this (about 10% of single VN women and about 30% of single USA women) then keep this in mind when panning for gold. Fortunately most VN women are not this way.
Anyone want to guess what portion of those "1 in 25,000" are not aware how gold diggers act? Not many. I can imagine that many of them when reading this thread will feel inspired to find themselves an American for $$$$. I suggest they stick with the lottery for seeking jackpot riches and have some self-respect and find a man for love/family.
And yes Dads who love their kids will want to do what is best for them. Moms who love their kids will work hard to make sure both parents have good access to the child and they will make it as positive and peaceful for the Dad to be more involved. Some Moms unfortunately misunderstand this. They fail to see how Dads who spend time with their kids do bond and then in their work/finances they then are always thinking about things they can do to help out their children more. When the child is used as a weapon then there might be some short term benefits for the vindictive Mom. But in the long run she is hurting her child. What she doesn't understand is that society, especially in America, will strongly encourage him to let go emotionally and look towards the long term future when the child is over 18. And then he will have 40+ years for positive relations free of the manipulations of that overseas vindictive person. That's why all women (except the narcissists) who love their children will strive to handle it this way. Yes the narcissists love their children but when push comes to shove they love their own greed more.
And yes there are bad Dads out there. I am not talking about them. I am talking about the ones who are trying to pay support and/or do visitation. Some do get scared away. Hopefully for the sake of the kids their parents can work things out and put the children first.