Definitely a put on, you can tell by the way she states certain things. Listen toward the end of the video you linked. They jokingly tell her that they're going to spread the word. Rather than respond like I feel she would if it was legitimate by saying something along the lines of, "Thank you so much." She went the extra step to thank them, and reiterate once again what she was thanking them for by saying, "Thank you, we need to move the deer crossing signs." As if people listening weren't aware what she was thanking them for.
And seriously, had it been real, they would have been laughing a whole lot harder than they were. I don't even think she's a good actor, I think it would have been a lot funnier if it wasn't so poorly done.