Hi and welcome to YT. I'm sorry your little one is doing so badly
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Don't give any more liver - it's *way* too overwhelming for many adult systems, let alone a young puppy. If you can, just feed cooked chicken and rice. Also give Nutrical.
Given the extent of worms this poor pup had, I imagine he is really very sick - and I think this will go on for awhile to be honest...he's going to need some time to heal. Stay in very close contact w/ your vet, and take him in again if he starts to go really badly.