Seems to be a misnomer on the thread title.
They weren't run down by a tug or barge, they cut between a tug and barge.
In the absence of a well calibrated
radar, and a qualified operator of that
radar it is vitally important that a) the watch fully understands light configurations and b) the skipper opts to sail with caution in busy waterways.
Let's be honest here. Assuming they were keeping a watch - the skipper opted to cut between two vessels that were moving at speed and only 900 feet apart.
6kts is roughly 600 feet per minute.
Seriously, they couldn't wait and pass astern?