Pet sitter fails to care for pets

[Catherine]

Those cats just barely survived. 

Signed or verbal the contract was between Olfert and the Benoits. There was no indication that there would be a subcontractor. 
Having hired a subcontractor, Olfert had an obligation to make sure the cats were being cared for. Sending reports that the cats were okay was misleading and dishonest. Olfert didn't know if the cats were fine. She did no follow up on the subcontractor.

The Benoits may be able to sue because they didn't authorize any one else to use their key and visit their home. They left the key with Olfert believing she would be in their house. I think there is at very least a breach of contract here and a violation of the Benoits privacy.
I hope they do sue Olfert. She should not be pet sitting in future.