downdraft plus recirc hood?

I am unhappy with my downdraft setup, there is a electrical junction up there for a lamp and I have been contemplating with a hood that doesn't vent outside. (recirc)

The other option is find out how I can connect a range hood to the downdraft vent inside the wall, that would be more destruction.

Is there a way to find out how the vent is routed. I can access the vent outside and it is around 7' high, wish I have one of those inspection cameras.