Okay, I am not an expert with older birds I got Charlie when he was a baby. I think Dorian needs to learn to trust you and get familiar with her new family and surroundings before you start to do any training. The step up command is important not only to handle your bird safely and in emergency situations but she sounds like she has not had a lot of human contact and really needs to gain your trust. Take your time, offer treats, sit near the cage and talk and just let her get used to you being there. Are you in touch with an avian vet? Have you enquired if they could possibly do a home visit? I think it is going to be a long journey but I can tell your determination and your heart is def in the right place:)