A building under construction in the Hudson Yards complex. Judy Zhu / for China Daily

One of them is Michael Sears, a principal in a small Virginia-based real estate investment fund management firm. He was awarded $14.7 million award for blowing the whistle on an EB-5 fraud perpetrated against Chinese investors by a Chicago-based businessman who claimed to be building a massive convention center and hotel complex near O'Hare Airport.

The businessman, 32-year-old Anshoo Sethi, amassed $158 million from 290 Chinese investors, promising each a green card.

In January, Sethi pleaded guilty to wire fraud, admitting he gave investors forged documents saying the project's hotels would be operated by Hyatt, which had no connection to the deal. Sethi, who faces up to 20 years in federal prison, has been selling properties to pay back investors, including the $41,500 administrative fee he collected from each (a total of $11.5 million).

None of the investors received green cards.

Griffin said one of the most controversial parts of the EB-5 program are the regional centers, what she calls "the people who group together investors, handle the paperwork and then funnel the money into particular investments."

The number of these groups that sponsor EB-5 projects has ballooned, going from 11 in 2007 to 588 in 2014 and 867 as of last month, according to the (USCIS).

But making the agency's headcount is not the same as getting their blessing. "The fact that a business is designated a regional center by USCIS does not mean that USCIS, the SEC, or any other government agency has approved the investments offered by the business," an SEC statement reads.

"As you have more and more regional centers coming online, we're seeing more and more frequently centers that are not fully complying," Reaz Jafri, a lawyer at the international firm of Withers LLP, told Forbes recently.

Regional centers

Alexander said that regional centers are one of the main reasons Congress has grown so concerned about the EB-5 program, "because that adds an extra layer in the process making it easier for people to not really know who they're giving their money to."

Republican Senator Chuck Grassley of Idaho and Democratic Senator Patrick Leahy of Vermont put forward a bill last year to curb fraud in EB-5 but it was put on hold and will be debated next month as part of the budget process, Alexander said.

Regional EB-5 centers have their counterpart in China with hundreds of so called "migration agents," who have been key in hooking up investors with some of the most successful EB-5 projects, but some are reportedly ratcheting up the finder's fees they charge regional centers.

The consultants can make up to $200,000 per investor, which works out to as much as a 40 percent commission on deals that start at $500,000 and range to $1 million. But, as The Real Deal reports, developers and regional centers continue to hire them, because they are the "gatekeepers" to thousands of wealthy Chinese eager to buy in, and get a green card.

Alexander emphasized that "no matter how sophisticated in their fields or powerful in their home countries hopeful immigrants are, they suffer a special sort of vulnerability when they risk their savings and to come to the US.

"The DOJ (Department of Justice) and the SEC have demonstrated their commitment to pursuing bad actors ready to exploit this vulnerability to line their own pockets," she wrote in an op-ed recently. "But these frauds are so destructive to hopeful immigrants — and so antithetical to American values — that action cannot come soon enough."