Keeping McKissic only makes sense if this is a PPR format.
Hilliard is a great stash who will become very valuable once the inevitable happens to Henry. That will probably not happen during the first few weeks, though, so you may have a chance to scoop him up again in 4-5 weeks. Unless he’s on another owner’s radar. FWIW, I have him in one of my dynasty leagues. In the other one, the Henry owner beat me to it.
Moss didn’t look bad at all last night. If that was really an indication for expected fantasy value remains to be seen, though.
Cook, on the other hand, should be in the dog house for the moment, though I wouldn’t completely write him off yet. But like with Hilliard, it will take some time before he becomes startable.