No guarantees once you leave my desk, how am I to know what you did once you left me. However, when the client returns you can see what state the nails are in, if there is clearly damage on the natural nail where the product has been prised or picked off then it's the clients responsibility to take care of them. If, however, you can see where you have caused the issues with things like insufficient prep causing lifting, poor stucture causing snappage, etc. then you need to correct those issues and rectify the problems. You will be able to tell from the state of the nails and some careful questioning of the client about what actually happened.
If she says she is heavy handed why are you taking the blame on yourself? She's admitted it's her behaviour.