It's not a competition between mentors, but between the individual contestant, so who ever is stronger should go to final round..Viswas was better. Anyway, this was bound to happen if HR was given a chance, we know the choice that HR does, by seeing the number of contestant left behind in his gharana. He got fair enough chance to chose good contestant in his gharana but he failed to do so, so how can he do it now.
Even I think Niladri and Vishwas (and perhaps even Abhijeet) were better choices than the people HR called back. Amongst the girls, he knew that Vineeta was sick so kind of acted politically correct, and first asked Vineeta to come (trying to show that he is fair) but he knew that ID will eventually call Joyeeta!! In boys, he knew that there were better choices around and so he never took a chance and called back 2 of his boys leaving the more talented behind! Vishwas and Niladri truely truely deserved to be in the finals!