Update on pet store rescue chicks

Well, so far so good (for the most part) The 10 chicks with the severe foot problems are all still alive, eating drinking and peeping happily. I have been changing their bedding pine shavings) daily and continuing with the antibiotics in the water. I have noticed that on one or two the foot has fallen off completely leaving just a nub. I have noticed a nasty smell coming from some of the dead feet though. No povidone/iodine in the house so will get some tomorrow to apply to all the dead feet/legs. Thankfully they all only have one afflected leg! Now I am wanting to have another coop/run built for when these "special needs" chicks grow up!
I am wondering if I should be offering them probiotics now, or wait until they are no longer on the Duramycin. Any ideas?
If they continue to do well I may be looking for special homes for some of these babies when they are older...if anyone in WI/UP is interested!

Gina