Salmonella in small cats

Hello
I have a problem. I bought some cat food 2 weeks back' since i have been feeding it to my kittens i have had 2 kittens die.. When i brought the 1st one to the vet they wanted to do extensive tests which would have been around $500-1200. I had taken my last 45 dollars to bring her in. When i called a vet office for the second kitten that came down sick i was informed to bring them to the humane society. I was accused of being an uncaring, er responsible pet owner. (I stopped feeding the food to my other cats and bought new ( At this moment i have 2 more sick kittens that i have been feeding homemade pedialyte & baby food soup. My question is: Is there anything else i can do to get these kittens through this? and how long does it take to flush salmonella out of their little systems? Salmonella poisoning is the only thing that fits all their symptoms... lost of appetite, lathargic, vomiting, dehydration, and death.