Bath panel has a crack - what might have caused this?

Hi, We are renting a house and the side bath panel has a crack at the top. A line about 10cm along. It looks to me like the panel is bowed all the way along, like the panel is too tall for the space its installed in and eventually a stress fracture has occured. We are wanting to be able to get a second opinion to present to the landlord when she inevitably tries to make us pay for damage caused by bad installation. IS there a way I can send photos of this and get someone to help our argument? Thanks we move out in a few weeks and I know from how she treated past tenants she will be looking to get all wear and tear paid for by us. thanks in advance Steve