I saw the video on a boating blog. The Cruise ship just ran down the excursion boat from behind. A clear violation of international COLREGs (IMO). The overtaking vessel is responsible for avoiding the vessel being overtaken.
FWIW we just did this evening cruise on the Viking ‘Skirnir’ about a month ago. It’s a dinner cruise where the ship leaves the dock and then cruises up and down the Danube for an hour or so, before coming back to the dock for the night.
After a day of excursions the next day, it leaves for Amsterdam the next evening.
I was setting up on the forward terrace that night and saw a number of these small sightseeing boats cut across in front of the Skirnir trying to beat them underneath the Margit bridge, one of them so close in front of us that I could no longer see the boat at all.
That’s what happens when you play chicken with a 443’ long river cruiser.
Visibility could be an issue here. Any reports about warning signals? Also, the larger vessel is much less maneuverable than the smaller one. Lots of unanswered questions so far.