I wonder why the tower just nonchalantly said there's nothing there if a crew reports seeing unexpected lights. How did they know a runway incursion, even by a vehicle, had not taken place ?
Well, because their tower is full of the latest, fancy equipment, so the single, very busy controller handling both GND and TWR, with 2 crossing active rwy's in use and a lot of activity going on even that late at night, will most likely has checked the rwy "
incursion status" on his fancy equipment and seen that all was as it should have been. And visual checking at night, at a 30-40° angle to the centerlines, would not have helped him easily spotting the misalignment... until AC actually overflew the acft's on C. And the fancy equipment '
loosing sight' of AC for about 15 sec's, surely won't have helped him either.