So sorry to read of the sick rooster Soctippy and your sick flock Fife.
Birds are more delicate than people realize, even with the very best care.
As far as worming sick chickens, I would just like to encourage people to find out what is wrong with their chicken so that you can give the right medicine and save it's life.
Sometimes a chicken needs antibiotics pronto to save it's life. Worming might be helpful or might not. I think it is very hard to guess and treat chickens. Even the veterinarians will check to see what type of bacteria is in the stool or what type of worm is in the stool. That way they can give the right medicine from many choices of wormers and antibiotics.
Not every chicken is worth trying to save but if you have one that you want to save, a fecal check is about $20 and can help you figure out what medicine to give. It can identify coccidia, gapeworms, giarrdia, some bacteria and all intestinal worms. I had a fecal check done on a sick hen recently. It showed NOTHING! I had to take her in and the vet listened to her chest and diagnosed pneumonia. Amoxicillan was what she needed. But her symptom had been loose stools - that was her only symptom.
If I had follwed the advice on BYC, I would have noticed the runny stools and wormed her with Valbazen. And she had pneumonia, so she would have died. She needed an antibiotic.
There are 4-H extention offices and MSU veterinarians and local vets who will have their technicians do a stool check for you. They do them every day for dogs and cats. Same parasties, same test.
Fife - what is M.S.?