Example: https://prow.ci.openshift.org/view/gs/origin-ci-test/logs/periodic-ci-openshift-release-master-nightly-4.12-e2e-metal-ipi-ovn-ipv6/1562677330093019136

I believe this was caused by https://github.com/openshift/origin/pull/27368

The tests were renamed, but they were referenced by their old names in the release repo either for skips, or possibly for other reasons I don't understand yet.
Most likely spot: https://github.com/openshift/release/blob/031c233818f7911be6b10ad058aadd5ff3ad1885/ci-operator/config/openshift/router/openshift-router-master.yaml#L106