Fix red develop 448f9b39d6c1

The merge lane found `develop` red at `448f9b39d6c105bb234e120633011541c5bdf483` on its own: no queued PR merges until it is fixed. Failing (tests and gate stages): - `tests/test_cross_org_isolation.py::test_every_path_parameter_is_swept_or_named` - `api-unit-dc-test` The whole gate log: artifact `9008` on lane task 9398. Make `develop` pass its full gate again. Open a PR as usual: the merge lane merges a PR that fixes some of these and adds no failure even while `develop` is red.

Named key_id (from the new API-keys routes) in the cross-org sweep registry and added a test that another org's key gets the same 404 as a missing one. Changed tests and quick gate pass. PR #6741 is queued to the merge lane. Memory: none applied.