We cannot pin-point on someone with just the knowledge of hearsay but the evidence that the people who argue about their theory being true do add up.
According to them, Mahesh Babu has been kept in an illusion by Vamshi Paidipally that the film really is his best business wise and producers couldn’t counter it with Vamshi managing to stick around Mahesh all the time.
Even though they know that film will be a costly failure and not really Mahesh’s best they had to play along as Mahesh could get unhappy with them if Vamshi is able to convince him, so much. Some might say Mahesh isn’t gullible but actors do tend to believe good things more than harsh reality as that doesn’t boost their ego.
Not many dare to speak to them with truth and that is how some directors make their way into the best friends list of the actors. Only a few can make it with brutal honesty. Producers are blaming Vamshi for making Mahesh say certain things so one-sided and they have spread their word against him, it seems. We don’t know how much this is true, but the producers are slightly relieved that Mahesh has gone for a holiday and now, they can look at things as they should be.