Seriousely. He went to the shop several times by train. They are not taking it seriousely. Oil leaking, drivetrain not working properly. Of course he is going to be suspicius and look for further damage, and also look for more problems since he is not happy with the bike and no longer trust the shop.
Why should he pay anything? He should have his train rides refunded and the bike phurchase sorted out one way or another. If there is sonething wrong (unfixable) with the bike I do not know but for sure there must be something wrong with the shop.