Udomdej, who stepped down as Army commander at the end of September after reaching mandatory retirement age, is the chair of the Rajabhakti Park Foundation.
Registered on September 16, this foundation is apparently designed to take over and handle the park's affairs.
"The foundation has not yet done anything. It's the Army that stays in charge," Prawit insisted.
When the scandal about alleged graft in the project broke earlier this month, Udomdej came forward to say that all panels involved were ready to answer questions.
He said demands for illicit kickbacks from foundries were detected during implementation of the project, but the problem had been solved - with the kickbacks
Funded by about Bt1 billion in donations, the Rajabhakti Park project has developed a grand park in Prachuap Khiri Khan's Hua Hin district and erected huge statues of seven former Thai kings under the Army's supervision.