Text after opening cutscene and also text in help tooltip specify, that they need to meet at the corner (coming from different streets). The idea is that they don't see each other until the very crash.
If they are going head on head on the same street, then they can see each other from the distance and just pass each other without colliding.
I wanted to add a special text or even a popup when they just pass each other, but did not have time for that.