As the sports director in the video from dash cam noticed, at one point riders entered a junction without any marshals closing off the road, which made them alert that something's not right and they immediately went on to warn to riders, shouting "Stay on the right side of the road" in Dutch many times, sensing that cars might appear in front of the peloton at the twisty roads.
That's precisely what happened a moments later, luckily it was in an open space where both parties were able to evade each other. However that doesn't make the potentially fatal mistake of the organiser any lighter and
UCI is very likely to take action.