Jenny's arrival didn't affect the atmosphere at the family gathering, but even added to it.
With just a few words, she solved a bunch of small problems Luke's grandfather, Drax, and Selina's father, Mario, had in running the ranch.
As one of the top business bigshots in America, she had plenty of manpower and resources. It was a piece of cake to solve the problems of running a "small" ranch.
In this regard, Luke couldn't compare with her.
He didn't rely on business to make a living, and his grandpa's ranch wasn't making a loss. It was just small issues in moving forward.
Secondly, Robert's misgivings were also dispelled by Jenny.
She promised that he would only need to attend certain meetings when it was absolutely necessary.
This might only happen once every few years or every decade — like last time, when Stark Industries shut down the weapons division, and Obadiah held a shareholders' meeting.