Stefano Domenicali has reportedly joined his F1 supremo predecessor Bernie Ecclestone in pressing for Christian Horner to consider quietly stepping away from Red Bull.
At the Austrian parent company's request, Horner, 50, met over eight hours last Friday with the Red Bull-appointed independent lawyer who is charged with investigating alleged "inappropriate behaviour".
Ralf Bach, the correspondent for Auto Bild, says the lawyer has now gone on vacation - with the outcome of his investigation currently unknown. The saga is tipped to drag on well past the launch of Red Bull's 2024 car this week and probably also the start of pre-season testing.
"What the allegations are specifically about is still not publicly known," he said. "The only thing that is certain is that the middle management employee, whose name is known but which we are not publishing for privacy reasons, felt under pressure.
"The manner in which the alleged coercion was carried out is not compatible with modern moral standards," Bach added, admitting that he - like most fellow F1 insiders - does not believe Horner can survive the scandal.
It was already known that Ecclestone, for whom Horner served as the best man at his wedding, has privately advised the long-serving Red Bull boss to step down.
And now it is believed F1's current CEO, Domenicali, is also getting involved behind the scenes on behalf of the sport's concerned owners Liberty Media.
"Even the Americans are putting pressure on Red Bull," said Bach.
"Stefano Domenicali called Mark Mateschitz at the request of his US bosses."
Critically, Horner is believed to retain the backing of the energy drink company's 51 percent Thai co-owners, but Mark Mateschitz - on the Austrian side of the shareholding - is the largest single Red Bull owner with his 49 percent.
And Mateschitz, Dr Helmut Marko and even the Verstappen camp are tipped to want Horner out - potentially to be replaced by Red Bull GmbH co-CEO Oliver Mintzlaff.
