If this is a nanny from a legitimate company, or a nanny who knows what they are doing, that wouldn’t be allowed. Most nanny’s would charge their regular rate plus an overnight fee plus charging extra when she has to watch Jackson since she is Oliver’s nanny only.
I think @fiveleggedgoat is correct in that they soon quit after a cruise because that’s the most time they are spending with them consecutively. At home, Jenn can get away with having Rosie handle Oliver all day because she can say she is “editing” or her and Tim have to go out and work (by working they mean eating and filming it). But on a cruise, Rosie is feeding Oliver his dinner while both his parents sit at the same table and stuff their faces.
She also was stuck on the ship with Oliver while Tim, Jenn and Jackson frolicked on the beach. She was stuck on the ship the whole time. I know she is there to watch Oliver but she probably thought she would get to watch him on the beach some of the time.
