Was that hunk of grasses in the crop or the gizzard...or both?
Do you have pics of the intestines and/or the abdominal cavity before removing most of the organs?
What kind of worms and with what and how did you treat them?
Hydro Hen is an electrolyte? Did he also have plain water available?
Don't over-do the electrolytes, one application is enough for a few days.
I would keep him isolated so you can monitor his intake and output.
Pull feed at night...