Slander about a Replacement at Work

My wife is going on maternity leave in a few months, and someone is being brought in to replace her. This person has already started training this week. During the two days she was there, she made my wife feel very uncomfortable, arguing about various things despite being told how things are done here. She wanted to do something on the computer, and my wife said it's not done here, so she called the boss, who of course said no. And so on with various things, constantly arguing, complaining of boredom, and wanting to do office work instead of learning how to do the actual work on the computer she'll need to use when she replaces my wife. In short, the question is whether it's permissible to call the boss and tell her everything, including all the arguments and the feeling that she doesn't want to accept authority and listen to the person she is supposed to replace. My wife is also afraid that when she returns, all her client files will be changed and in disarray.

Hello,

If there is a genuine concern that the office will suffer from employing this worker, it is obligatory to inform the manager, according to the law of returning lost property.

You must convey the story as it is, without additions or interpretations, and express your concerns. Not in an absolute manner, but in a way that suggests the need for attention.

Book of Chafetz Chaim, illustrations at the end of the book.