Rescue etiquette? Choosing a new pup ?

If Lillie is like most rescue people, she will be thrilled that you found the perfect dog for you and that you adopted instead of buying. I would go ahead with the adoption of Flash, but do make sure and let Lillie know so she is not still on the lookout for a puppy for you. If you'd like, to ease your conscience, make an adoption to Glen Highland Farm, they would appreciate it and you could feel that you were compensating them for all their work in trying to match you with a new companion!