I made this mistake a couple years ago. I still regret it.
My car looked good when it got back, but everything else was wrong. Premixed coolant was mixed again, thankfully I figured that out before it got cold. I think it was around -12C I measured.
The plastic splash tray under the engine bay was damaged. They tightened the bolts so hard they went through it.
The AC condenser was trashed in the accident, strangely less than a year later the new one started leaking. The compressor was also seized. Although I can't prove it, I suspect that they did the bare minimum by replacing only the condenser and there was metal debris in the system. I wasn't about to go back there, so I got to foot a bill of about $2500 CAD.
And the worst part? I did confront their manager on this nonsense. He didn't care. Tried to tell me that everything was just fine.
Never trust your insurance company. They will always go with the lowest bidder.