Quarantine escapee, do I need to worry?

If this is in wrong place I am sorry but it didn't seem like an emergency so I wasn't sure.

Ok, so I got a pair of bantam cochins from the fair (yeah I know bad place), they are in quarantine on front porch. The other chickens can't get up or near them as they only fly to roost and no one goes directly from porch to free range area, so it was the safest quarantine area to put them in cage. Well one of my dads friends got a gag gift for birthday it was a polish hen so I said I would take and put in quarantine with my new ones for a month. That worked for a day, the cochins don't want it with them they pick on it and its miserable. So I got out another cage which I thought was secure put it in there next to cochins. It stayed in cage perfectly fine all day and gave me no reason to believe it could escape. So I left to take my fiance dinner at work. This was about 6pm so pretty close to the time that everyone goes in to bed which is about 7pm. The free range chickens were all near the coop which is behind the house and about 500 ft back. I got home around 8:30pm and its still a little light out. As I am walking up to the house I notice a black thing on the kids slide get a little closer and see a white spot on the black thing, man she escaped her cage while I was gone. Ok so I pick her up and take her directly back into the house. So she made it about 50ft from the porch. Was in the back but not near coop. I sprayed disinfectant on the slide but can't know where else she would have gone if anywhere. She doesn't seem to be sick and the original breeders of these chickens are top breeders for those breeds in this area and very reputable. She did have one watery eye but I am fairly sure that it was her crest poking her eye, as I trimmed it so she could see and it stopped being watery. I haven't seen any lice or mites on her, she hasn't sneezed or coughed and she has normal poop. Now that she can see she eats and drinks normally. Obviously I am still keeping in quarantine until her month is up its only been about a week. How likely is it that if she does have something that my other chickens could get it? I don't think they were together because there is no way my roo would have left her outside.