When Chin and Kono are talking to Mr. Weiss, he has just had his ears cut off and a bandage around his head--covering where his ears were. When the camera angle changes, it shows him in bed with his ears clearly visible. The camera angle changes again showing the bandage around where his ears should be.
When Chin and Kono are talking to Mr Wise in his hospital bed he can hear them clearly despite having both ears removed and a bandage wrapped around his head.