Steve Wynn’s plans for a $4 bill casino in Macau, included a $50 million payment by Wynn Resorts to a little-known company with ties to top officials in the Chinese territory and a prominent Beijing family, according to a report in The Wall Street Journal.

The complex deal dates back seven years and provides yet another window into the murky world of U.S. casinos doing business in Macau, a booming but corrupt enclave that generates five times the revenue than Las Vegas.

Billionaire casino mogul Steve Wynn sat for a lengthy interview with The Journal at his Cafe Esplanada casino in Macau, where he brought along two lawyers, two board members, two bodyguards and his wife. Wynn explained the company checked out the people they were dealing with and “everybody came up dandy.”

Wynn’s company is already under investigation for its business practices in Macau. The Securities and Exchange Commission is investigating a $135 million donation Wynn’s company made last year to the University of Macau. The company said the donation was legal and consistent with the company’s tradition of philanthropy. The university said the gift will support activities at the school’s Asia-Pacific Academy of Economics and Management.

Wynn is also embroiled in lawsuits from a former board member and shareholders, involving allegations of wrongdoing by his casinos in Macau. Meanwhile, Wynn’s rival, the Las Vegas Sands, is under investigation by both the SEC and the Justice Department for possible violations of the Foreign Corrupt Practices Act, which bans bribery by U.S. companies abroad. Las Vegas Sands denies any wrongdoing and says it is cooperating with investigators.

Last week, a former executive alleged that Sands’ chief executive Sheldon Adelson approved a “prostitution strategy” at his casinos in Macau. Adelson denied the allegation, which is part of a wrongful termination suit brought by the executive.