With Path Selection, what happens to traffic destined for a remote site where no uplinks...

Remote uplink configuration is not needed so path selection will be applied normally.

Traffic to that site will be blackholed as there is no path back to the source site.

The local Steelhead will probe the remote Steelhead for its default gateway.

Only the default path can be used as the Steelheads on each site won’t be able to agree on a path.