I am sorry for your loss.
IYou need to treat your entire flock for coccidiosis at the same time.
Not one bird here and there.
If the coccidiosis is not caught quick and treated it will tear up their insides and kill them.
How much Corid are you putting in the water?
You gave Safeguard for 5...
Coccidiosis is what I say too.
Exactly how much Corid did you use?
When you say you tried worming everyone...what exactly did you use and how did you give it to them?