i, too, have a ds w/peanut/tree nut allergies... we have been in goofy's but every time it's been a disappointment... even the bagged stuff was not safe, as it was manufactured in a facility that processes peanuts/treenuts... the only safe thing we found were little tins of mints (big deal! not!)
what we did find, however, was that a few wdw locations were starting to carry the divvies brand of treats which are safe for nut allergies... we found them in main st bakery in mk and the food court at cbr (not at bc/yc food courts, btw)... we stocked up when we found them so when the other kids were hitting the candy co. ds had some sweet treats to choose from...
good luck!