The train Moshol just demonstrates one of the weirder consequences of the theory of relativity known as the “relativity of simultaneity.” Practically this means is that events that are simultaneous to one person are not necessarily simultaneous to anyone else.
In the train Moshol to the guy on the platform both strikes ACTUALLY happened at the same time. He knows this because if he measured the distance traveled by the light from each strike and the speed of that light he’d see that they both traveled the same distance at the same speed and hit his eyes at exactly the same time.
For the guy on the train the strike happening on the end of the train in the direction of the trains movement relative to the platform ACTUALLY happened first and the strike that happened at the opposite end of the train ACTUALLY happened after. He knows this because if he was to measure the distance and the speed traveled by the light from the strike in the direction the train is going he would see that it covered the same amount of distance as the strike at the back of the train at the same speed as the strike that hit the back of the train (the speed of light is a constant) and the light from it still hit his eyes first.
Neither the observer on the platform or the observer on the train are wrong. On the train the strikes were not simultaneous and on the platform they were.
It’s amazingly weird and the consequences get stranger and stranger the more you think about it.