It seemed to me that he heard it all.
AngelDark, I agree with you. Seems he heard it all but is reserving his opinion or action. Why I have no clue.
Could be that his emotional tumult with regards to Krishna has so seized him that he is not able to use his senses properly. To him, its like there is an abyss that he cannot cross over to meet Krishna and so nothing else much mattered to him. But, definitely expressions have been misleading and I can only attribute a surprise element for the viewers in that impassive expression.