The net-revenue example relies on several linked concepts agreeing, so I would make validation operate on the bundle as well as each Markdown file. A definition can be valid YAML while linking to a schema field that was renamed or to a policy outside its declared scope.
A CI check could resolve every internal link and validate the referenced field identifiers before publishing a bundle revision. Then the runtime records that bundle revision with its evidence plan. This makes the proposed Git review cover relationships that otherwise fail only when an agent tries to traverse them.