You haven't had them long enough to know they are healthy. If you don't understand that you need to quarantine new birds, I certainly wouldn't want to risk my flocks heath with them.
I would guess the woman you got the free chickens from. In your blog (you link as your website) you say:
"So, I got online on craigslist and there was an ad for 30 free hens and roosters not far away, so I called and even though we had just got home and just sat down, we gathered up our cages...