How can I feel confident that diagnosis is correct? on 2001 Buick Century

Brown Automotive diagnosed "oil in coolant with internal engine light" as internal engine damage (possible cracked head or block or head gasket but not the intake gasket). Their paper-work shows "34 engine cooling" and "32 engine mechanical". They recommend an engine replacement. Should I consider this an accurate assesment or get another opinion?

Get Your Car Fixed at a RepairPal Certified Shop.
We certify shops based on expertise, quality work, and verified customer reviews
1 answer 1 comment
Is it oil in the coolant (visible in the radiator and coolant reservoir) or coolant in the oil??
Big difference between the two and one maybe an easy repair.
Let us know which one.

Zee
I wanted to ask Zee if I have oil in the coolant that is visible in my radiator and reservoir what does this indicate to you?? thank you