That's complete bullshit. No way should he have pay up to 1.2 MILLION dollars for failing to make weight - I'm sure it wasn't intentional.
This could be either good or terrible new to Hatton, depending on how it affects Castillo. If it distracts him and weighs on his mind, it could spell trouble for him; but if he uses it as something to feed the fire and motivate him, Hatton could be really in for it.