Maybe it's embedded in the concrete support that runs all around the mound? Or is it on the ugly green bridge, almost crushing the poor stones below? Maybe it's sat on the tour bus? Is it watching from the security hut? Is it hanging around the informative chronology plaques? Or is it hidden behind the cordon, restricting access to the top of the mound?

No, I reckon it's in the souterrain which Newgrange™ enterprises so kindly allow you to crawl through.