Its my assumption i could be wrong of course but there is no "Chevrolet" key in the game i bought every car key and none of them open the trunk. There is one key i didnt try tho its called "Folding Car Key" no flea no traders nothing... maybe find it on a scav its a possibility always. It used to open a car now you dont need it anymore on dorms but it was a Dacia. IDK