Wonder why it took so long to take people off - the severity of the damage surely must've been clear quite rapidly, so a 3 hour delay seems a bit much?
It is safest to remain on the train. A good
TM‡ would communicate as such. If they couldn't get people safely onto another service until 2 am it is best to keep them on the train rather than the platform. It won't have been a busy service. Get them all to the opposite end of the train, presumably first class direction, near to buffet. Supply some drinks biscuits etc. The fire brigade won't want people getting in their way!