The flight descended below 100 feet above the ground and initiated a go-around after overflying the first airplane on the taxiway.
NTSB wording sounds like AC759 overflew UA1 below 100ft while descending or floating above the taxiway. And once UA1 was behind them they applied go-around.
What I can't grasp is that UA1 saw AC:
"He's [litterally] on the taxiway !"
But, until flying past UA1, AC didn't noticed that the lights on the "runway" were those of the 4 taxiing A/C ??
Hopefully CVR and FDR were downloaded in time by the authorities.