An example of a failing job is here https://prow.ci.openshift.org/view/gs/origin-ci-test/pr-logs/pull/openshift-metal3_dev-scripts/1336/pull-ci-openshift-metal3-dev-scripts-master-e2e-metal-ipi-serial-ovn-ipv6/1487015648352538624.

The problem seems to be in a timeout when deleting the extra worker. This can be seen in the BMO logs:
2022-01-28T13:13:58.795923165Z {"level":"error","ts":1643375638.7957456,"logger":"controller.baremetalhost","msg":"Reconciler error","reconciler group":"metal3.io","reconciler kind":"BareMetalHost","name":"ostest-extraworker-0","namespace":"openshift-machine-api","error":"action \"deleting\" failed: failed to remove finalizer: Operation cannot be fulfilled on baremetalhosts.metal3.io \"ostest-extraworker-0\": StorageError: invalid object, Code: 4, Key: /kubernetes.io/metal3.io/baremetalhosts/openshift-machine-api/ostest-extraworker-0, ResourceVersion: 0, AdditionalErrorMsg: Precondition failed: UID in precondition: 744462c8-35f4-4654-8645-2f80c700ff24, UID in object meta: ","errorVerbose":"Operation cannot be fulfilled on baremetalhosts.metal3.io \"ostest-extraworker-0\": StorageError: invalid object, Code: 4, Key: /kubernetes.io/metal3.io/baremetalhosts/openshift-machine-api/ostest-extraworker-0, ResourceVersion: 0, AdditionalErrorMsg: Precondition failed: UID in precondition: 744462c8-35f4-4654-8645-2f80c700ff24, UID in object meta: \nfailed to remove finalizer\ngithub.com/metal3-io/baremetal-operator/controllers/metal3%2eio.(*BareMetalHostReconciler).actionDeleting\n\t/go/src/github.com/metal3-io/baremetal-operator/controllers/metal3.io/baremetalhost_controller.go:542\ngithub.com/metal3-io/baremetal-operator/controllers/metal3%2eio.(*hostStateMachine).handleDeleting\n\t/go/src/github.com/metal3-io/baremetal-operator/controllers/metal3.io/host_state_machine.go:530\ngithub.com/metal3-io/baremetal-operator/controllers/metal3%2eio.(*hostStateMachine).ReconcileState\n\t/go/src/github.com/metal3-io/baremetal-operator/controllers/metal3.io/host_state_machine.go:199\ngithub.com/metal3-io/baremetal-operator/controllers/metal3%2eio.(*BareMetalHostReconciler).Reconcile\n\t/go/src/github.com/metal3-io/baremetal-operator/controllers/metal3.io/baremetalhost_controller.go:247\nsigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller).reconcileHandler\n\t/go/src/github.com/metal3-io/baremetal-operator/vendor/sigs.k8s.io/controller-runtime/pkg/internal/controller/controller.go:298\nsigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller).processNextWorkItem\n\t/go/src/github.com/metal3-io/baremetal-operator/vendor/sigs.k8s.io/controller-runtime/pkg/internal/controller/controller.go:253\nsigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller).Start.func2.2\n\t/go/src/github.com/metal3-io/baremetal-operator/vendor/sigs.k8s.io/controller-runtime/pkg/internal/controller/controller.go:214\nruntime.goexit\n\t/usr/lib/golang/src/runtime/asm_amd64.s:1581\naction \"deleting\" failed\ngithub.com/metal3-io/baremetal-operator/controllers/metal3%2eio.(*BareMetalHostReconciler).Reconcile\n\t/go/src/github.com/metal3-io/baremetal-operator/controllers/metal3.io/baremetalhost_controller.go:251\nsigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller).reconcileHandler\n\t/go/src/github.com/metal3-io/baremetal-operator/vendor/sigs.k8s.io/controller-runtime/pkg/internal/controller/controller.go:298\nsigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller).processNextWorkItem\n\t/go/src/github.com/metal3-io/baremetal-operator/vendor/sigs.k8s.io/controller-runtime/pkg/internal/controller/controller.go:253\nsigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller).Start.func2.2\n\t/go/src/github.com/metal3-io/baremetal-operator/vendor/sigs.k8s.io/controller-runtime/pkg/internal/controller/controller.go:214\nruntime.goexit\n\t/usr/lib/golang/src/runtime/asm_amd64.s:1581","stacktrace":"sigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller).Start.func2.2\n\t/go/src/github.com/metal3-io/baremetal-operator/vendor/sigs.k8s.io/controller-runtime/pkg/internal/controller/controller.go:214"}