It seems it would be an accident due to negligence. It's definitely an accident.

To me, either your auto or homeowners policy, possibly both, should cover this. Your deductible might be too high for much compensation though.

You probably already know most of this already but this site has some good info:

https://www.investopedia.com/financial-edge/0211/what-to-do-when-insurance-companies-wont-pay.aspx

Long ago I had an insurance company that refused to pay. They quickly paid after one letter from an attorney.