I couldn't disagree more.
Teams were not desperate at the draft. Someone will be desperate when their main back gets hurt.
Henry may in fact be the third best available back, but he is the best cap-friendly one when most teams dont have the cap space to sign the best available back when their star gets hurt, especially if they just plan to use him to fill in so their season isn't tanked because their back is out for 4-5 weeks.
You say Henry is useless to the Bills so we won't get much for him. I believe it is not his value to the Bills that determines his value, but his value to some desperate team. It will happen. There are 32 chances someone will get hurt in the preseason, and Henry is a good bet to replace him.