Genetic mutations are passed down through generations. If the man's genetic material mutates then you will see it in his kids, grand kids and beyond. Thee is absolutely no reason to believe it will stop with the grand kids.
Recently they located a gene responsible for giantism and it has run in four families in Ireland for hundreds of years.
Right now they have not yet had a chance to test great grand kids,they must get born first, but I would not be surprised to see it continue on. That is the nature of mutations.
Now I recall their worry about about small dioxin spills and that is the same chemical in Agent Orange. This is the same chemical used in farming to case cotton plants to lose their leaves before the cotton is picked by machine. Now according to what I have read on Agent Orange it was about a thousand times more consecrated than what is used on cotton crops.
I myself suffer health issues caused by Agent Orange and the VA only finally got around to admitting it five years ago. I was exposed to it in Vietnam in 1966 and 67.
So far I have suffered four cases of Pancreatitis, the first one landing me in a hospitals for over a year and nearly killing me, and that lead to me becoming diabetic, and that has led to five operations on my right eye, which I am no longer able to read with and was blind in twice so far. Now I start needing an operation in my left eye, but they are afraid to do so because of the complications I suffered in my right eye. I also started tripping and nearly falling the same year as the pancreatitis, which continued till I was lurching into things hard enough to bruise and then falling four years ago, now two years of using a walker. Meanwhile I have blacked out twice while driving and had to give up driving. That is a considerable price to have to pay for serving my country and then having to fight the VA every step of the way. No one else in my family has had these problems.
Fortunately I never had any kids, so I have not suffered from seeing birth defects in them.
Remember that this report stating birth defects to the grandkids was put out by the VA, so it most likely understates the problem as that has been the habit of the VA since it was created. Once it admits to a problem it becomes its responsibility to take care of it which depletes its always inadequate budget.
It takes up to two years just to get the new vets into the VA system to even begin to get any treatment.
Wisdom is what is left after you have done all the dumb stuff.