Maybe not. They were told to leave. She called police. They would more than likely be considered trespassers.
The lawyers will get a structural engineer in there. This has big money settlement written all over it. She rented the place out, she’s cooked. The homeowners insurance would need a rental rider on it.
The insurance company will get out of it the best way they can claiming they do not cover rental liability. They’ll get dinged too.