He said he had stopped working with the Chow sons before they applied to university.

Zimny said his services can also include brokering introduction meetings between potential donors from Asia and development officials at U.S. universities, adding that schools welcomed these introductions as a way of fielding multitudes of donation requests.

In his view, "Money is money, whether it's coming from a random family in Hong Kong or a fifth-generation Whitney applying to Yale." He added that donations have to be presented "in a way that doesn't look like quid pro quo."

Consultant Susan Joan Mauriello disagreed, saying she has heard of donations making a significant difference in admissions decisions only in "development cases," which involve families with multiple generations of alumni that have made significant donations over the years.

Harvard declined to comment on whether donations influence admissions decisions.

The IECA said "no educational consultant will act as a middleman for donations to a school," adding that consultants "will put the family directly in touch with a university's development office and donations would be made directly."

But the appetite among Hong Kong's elite for getting their offspring into top universities is unlikely to fade.

"The way to differentiate yourself is "that one line on your resume that says what university you came from," Capstone's Po said. "That's one of the few elements that sticks with you for the rest of your life professionally."