Storing a bear roast after cooking in a crockpot
If your crock has a warm that you can trust is above 140 F but not so hot to cook it down then you can leave it in the crock.  Otherwise you need to get it under 40 F.

A better option would have been to start it at a time so that it finished at 6 PM.
Why not just start it 8:30 AM?   

If you are going to cool then remove from the crock pot as that is a lot of heat to put in a refrigerator.