as far as that is concerned the primary step of routing it through Dooars was not required if u are not giving any commercial stoppage.And if u are giving such via EC u should have given a stoppage at APDJ or New Mal Jn which would have served the purpose.Again when u are diverting it through NCB it will surely get preference on the behalf of other trains and will take even more than 30min less which is quite irrelevant when the train is getting late by 10 hours.But again not giving stoppage at NCB doesnt works and at most of the times it needs to halt ao it is a kind of a very tricky situation