It is too late now but what I would have advised is to "test drive" this dog. By that I mean take the dog for one day or one night to see how it behaves in your home. Even though the owners were honest enough to tell you about their dog's SA, 15 days is a long time.
I've sat for SA dogs before and it is not a pleasant experience. Thankfully none of them were destructive, but sitters have posted numerous times here about major damage to their homes. I once worked with a neighbor to get her dog acclimated to staying at my house. Our dogs were friends and they only lived across the street. She would drop him off for a couple of hours a day. Unfortunately we never completed this training work but he was unable to stay with me. Instead they now hire a house sitter and their dog is much better with that situation. He has also been on doggie Xanax.
Medicating such dogs has to be started well in advance of the boarding date. So that isn't an option and I don't think it is effective.
I've seen a couple of episodes of Lucky Dog in which Brendan worked on dogs with SA. In all cases, he used a combination of meds and intensive training.
Since the owners know the dog has SA, you should find out what methods they use. Does the dog have SA at home or only when staying with strangers? How many times have they left her in the care of others? What has happened when they did? How destructive has she been? I'd look for answers to those questions.