With regard to the toilet training, I would suggest that the dog is taken out to 'do the necessary' and then comes back into the house, and into an indoor kennel. She should not soil her own space. After an hour or so, your friend can take her outside again to see if she will go, outside. Always use the same place outside so that the dog gets to know it's hers. If she won't go outdoors, try getting your dog to use the designated space, and your friend's dog will then scent mark over it, to claim that space for herself. It is possible that the soiling indoors is a dominance thing; a showing who's boss.