Would be a real coincidence, but not completely unlikely in these times. Each country in Europe has it's own train control system operated locally, there's plenty of systems in place in each system to prevent head on collisions, but nothing is fool proof, I guess if a controller dies suddenly things like this can happen.

Another scenario would be the engineer, all trains has a "dead mans switch" supposed to cut power in case the engineer dies suddenly, yet in many cases the engineer puts a brick on that allowing the train to continue if they die suddenly.

There's also generally much higher speed involved, which in itself adds to the risk when the consequences of a mistake happens faster too.