roblagatta, thank you so much for looking into this. As far as I can see, the code is all the same:
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She is adding the code into the HTML window, so it's not a plugin. I've tested by adding an extra </div> tag as it acts like it has an open one, but that just broke the page. She also said that before she added Groupon, the PayPal buttons were doing the same thing. On all of the calendar/list pages, the top entry has no button, but it is showing up at the bottom of the last entry.
My gut is telling me that there is a conflict with that many of the same exact scripts running on the same page. All of the Groupon scripts are the same.
Could it be a conflict with the script and the Event Calendar code?