Steve Wynn and his legal representatives set up a company separate from his Wynn Resorts Ltd., according to public records, that helped conceal a $7.5 million payment to a woman who had accused the casino mogul of forcing her to have sex.

The limited-liability company, called Entity Y, was created in 2005, Nevada records show, after a manicurist at Mr. Wynn’s flagship Wynn Las Vegas casino-resort made the accusation, according to people familiar with the matter. Entity Y was created solely as a vehicle to handle the settlement funds, a Wynn Resorts lawyer confirmed to a judge in a hearing in October, according to a court transcript.

That hearing was part of continuing litigation between Mr. Wynn and his ex-wife, Elaine, over her bid to lift restrictions on the sale of her stock in Wynn Resorts.

Mr. Wynn used his personal funds for the settlement, his lawyers said in an earlier court filing in that case.

The size of the payment and the allegations surrounding it were first reported by The Wall Street Journal in late January. Regulators in Massachusetts, who are investigating the allegations and who have the power to revoke the company’s license there if they determine Mr. Wynn isn’t a “suitable” casino operator, said last week that the settlement and any efforts to conceal it from regulators are a “critical element” of their review.