We've done the numbers already, remember MD?Your mathematical world is incorrect.
How do you explain the fact that lightening struck A and B simultaneously, the speed of light is measured to be c in the train in each direction, the observer on the train was at the midpoint, and the lights impacted him at different times??
Tell me how you explain that, in your delusional world that is Einstein's.
The train observer uses a different synchronization standard.
Both observers agree that according to the embankment standard, the strikes were simultaneous.
Both observers agree that according to the train standard, the lightning strike at B occurred first.