If I start at the CiviCase dashboard, select "All Cases", then select a Status - I get the search results that I would expect. Something like all the cases of Type X that have status "Awarded"
If I select All, and then Export Cases from the Actions menu, it exports all the cases of any status or type.
The export works as expected from any other search or if I use "My Cases" from the Case Dashboard. I'm thinking this must be a bug, but I'm unsure!