Huh...yeah that would work but it does seem a bit fishy doesn't it?
Usually I would think you would have a molex splitter down there & hook this lamp in to the wires coming down from the PF/slot machine light. Technically you could attach them above, if there's room under the plastic, or you could pierce the wire leading up with the clips so they make contact with the copper.
Not exactly the best options, but unless there's another power source going to that lamp I can't think of a way to do it.