For being able to connect to spire outside of the cluster we need ZTWIM to create a Route to SPIRE server. 
For example: 

apiVersion: route.openshift.io/v1

kind: Route

metadata:

  name: spire-server

  namespace: ${ZTWIM_NS}

spec:

  host: ${SPIRE_SERVER_DOMAIN}

  port:

    targetPort: grpc

  tls:

    termination: passthrough

  to:

    kind: Service

    name: spire-server

    weight: 100