Root insurance wants to give me estimate based on photos

Someone rear ended my parked car. They have Root insurance and I filed a claim. After providing photos of the cosmetic damage, they said they will provide an estimate in x days.

This is new to me as I thought insurance would ask you to go to one of their shops to get an estimate. My main concerns are:

1. I want to get the car checked out by a mechanic just in case there are damages beyond just cosmetic that would affect the long term driveability. I want the underside to be inspected.

2. I read that Root often makes a lowball offer based on the photos.

I hope to get some advice on how to proceed and what the next steps might be.

Thanks.