Red I don't see how the grad student will think less of you. I am imagining that he is fond of you both. Your H is putting him in a high pressure, uncomfortable position. I am sure that the grad student will feel uneasy and guilty if he goes along with your H's wishes.
Thanks, newmama - that does help. He's a good kid who just went through a VERY emotional breakup with his girlfriend, so I'm sure this must be very uncomfortable for him.
One of the other grad students who dislikes OW hurried through her studies and left last year because she lost complete respect for my husband, her mentor. So sad...