The actions of the cleaner, and his conspiratorial nod to Holt does raise suspicions. However, I cannot make out a teleprompter in those videos. I can certainly believe they did it; but I do not see it.
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It’s on this video - teleprompter is inside the lecturn/ podium and is revealed as a band of light. The person on the video shows it well, several times.
1:37 Minutes
HILLARY DEBATE TELEPROMPTER CAUGHT ON CAMERA
https://www.youtube.com/watch?time_continue=97&v=rzTeRZ9M_lU
Another video..............https://www.youtube.com/watch?v=JsriYyuigVo&feature=youtu.be