Carglass: Problems with accepting car disc exchange!

I did not find a suitable forum. I had the following problem with Carglass. It had to be changed with my 1 year old vehicle the windscreen over partial cascade. When accepting the vehicle, I requested the note in the order that my car was delivered without damage to body, dashboard, roof sky. It is actually common during an inspection. Does not want to avoid stress that – if during the WS change – this does not occur. was denied to me! Without any proof! Is that so usual? How else could I prove any defects that they were not before? Photos? Thank you