Yes I thought it was pretty clear the offer was cash, and you could see her considering the various things she might do with it! Unless books happen to be her thing, she might have been disappointed. I guess it might be a legal thing, though, that they couldn't give her actual money - though she must have been offered something for doing it in the first place, even just a gift.
I am surprised they still allowed Sam to take the points for that, though! Also it was a kind of bizarre task, given that the child was old enough to know that she was trying to see people pretending to sleep, so she must have known that they were all pretending really and it was more a task of trying to choose who was the best pretender, rather than trying to convince her they were really asleep. I thought it was going to be a toddler who could come up and interact with them, which would have been funny.
I also thought that there was going to be something made of the fact that one or two of them read the task as sleeptalk and others as sleepwalk. The 'talk' bit was highlighted in red, so I presume was wrong, and the 'walk' bit in green, but nothing was said about that again.