Only option remains is to change boarding point and board from Gorakhpur. Not that it'd be bad to keep it as it is, changing boarding point would simply be a measure against bureaucratic lethargy as we might end up facing a flock to corrupt incompetent pricks. It's better to be safe than to get involved in conundrum of "procedures"
390 rupees loss vis a vis 3200 rupee ticket is not something crazy, sometimes things are simply unavoidable. Especially considering the distance he needs to travel.