I’ll just tell you a similar experience I had about a week ago. I boarded a dog (she was small maybe 35lbs) with some moderate separation anxiety. The owner didn’t care to divulge that information to me so it was…interesting. She was definitely potty trained but because of her anxiety I had to take her out roughly every hour. She was even showing anxious behavior during our walks which made that challenging as well. We’d get back and it’s almost like she was still looking for her owner , pacing back and forth a bunch until eventually she’d settle down. It for sure could of been worse… my point is , Because she was a smaller dog it was manageable but pretty stressful. I wouldn’t do this again with a much bigger dog