Notice how other judges keep on praising other contestants, but when it comes to Bappi da's gharana, there is ALWAYS some marks missing for both the girls. Even when both these girls sings the best, they get to hear "you can improve, etc" comments.
Think about it. Bappi da had to take this step today since both of his students were in bottom two. It was more of a "im pissed of by these (biased) judges, who never speak a word of praise for my two girls" rather than a biased view towards mauli alone.
Seriously, im in no way trying to defend Bappi da. Infact im only defending sumedha here; that she's even BETTER singer in bappi da's eyes than mauli. That is why he chose her to record a song with and not mauli.