Out of interest, what is the track layout like at this station? I think it makes a difference if there is a refuge you could stand away from any (frequently used) track - eg where previous track has been removed, like at Andover. I don't suppose this was the case here?
From memory, it's been a while since I was last there, you can see clearly in both directions and would see any approaching train, no there is no sort of refuge between the two tracks.
We can argue this forever and a day but the bottom line is that four reasonably fit blokes would have been able to jump onto the track and lift the lady and her wheelchair and themselves back onto the platform long before any train was approaching, indeed it appears that is excatly what happened................so what exactly is the problem?????