Reb Eliezer,
a) who said that if it was a tinuk shenishbah that changes the Halacha in regards to this case?
b) the article says his father is frum but his father’s brothers (who are business partners with the father) are not frum. Therefore those brothers were likely brought up frum, but even if not they are clearly exposed to frum life — which means that they are NOT tinuk shenishbah.