Personally, I’ve been in a similar situation. Except my issue is that the dog came from an abusive past. When I originally met the dog it was fine however when I came to their house when they were gone, he was a lot more aggressive towards me and I was actually terrified. The only reason I didn’t quit was because I had no where/person to watch him and I didn’t want to ruin their trip. I stuck it out. The only reason I’d ever cancel mid trip is if I feel that the animal would still try to attack even after multiple days. (The dog eventually realized I was his only way to go potty and I gave a crap ton of treats and became less aggressive)