It has been noticed by some of the Global Sysops (who are graciously helping with monitoring of Foundation Governance Wiki) that their rights do not provide them with Translate Admin rights on that wiki - which prevents them from being able to delete translated pages.
We should fix this specifically for GovWiki - but perhaps this should be fixed for all future uses of Translate extension on Foundation hosted Wikis?
UPDATE:
Code-level assigning of Translate Admin rights to Global Sysops specifically should not be done via code. There may be some rights related issues to resolve to get Global Sysops access to provide support.
Adding 'edit-legal' rights to Translate Admin group should resolve this issue for Translate Admins (including Global Sysops with those permissions) on GovWiki.