Unhappy!!

My vehicle went to Honda Westrand for a replacement part (oil control arm switch) as my engine light kept coming on while driving. When i collected my vehicle my windscreen had a huge crack! Honda Westrand says they didn't drive my car even though I have an e-mail confirming that a technician has gone out to test drive my car to make sure the problem has been sorted out. They offered to pay the excess for replacement, but i feel that they should replace it and not expect me to claim from my insurance?