He can say he was preparing for entrances but if he started justifying his MBA than that would directly raise questions like...
> If u dont want to be a part of bgrade bschool than Y did u joined it.
This shows decision power was not their.
> Now you want to change it into good bschool.
This shows one cant manage the situation and turn out to be best in what he got,instead we facing backward and changing the path.
But if he completes his MBA and work in industry even for 1+year and than he can move ahead with 2nd time MBA, in that case one would be able to reply properly and that justification would be more valid and valuable. One guy in my Class is an MBA and now doing double MBA

And even he was from bgrade or say cgrade institute.