EXCLUSIVE: The truth from the top on West Ham star Jarrod Bowen after the Mail’s devastating claim ahead of the second leg with Bayer Leverkusen. As far as having a mountain to climb goes it’s not quite Everest but it’s not far off for West Ham this Thursday night. The Hammers have it all to do when they take on the newly-crowned German champions in the second leg of their Europa League quarter-final. West Ham will be hoping that Leverkusen have a hangover from celebrating their first ever Bundesliga title. David Moyes’ side know they have to somehow claw their way back into the tie at 2-0 dow…