The reason there is no cluster information was that there was an identification rule on u_cmdb_ci_ibm_cluster with identification attribute cluster_id.

On the discovered cluster this field was not populated.

To seethe identification rules:

1. Navigate to CI Identifiers
2. Look for records that applies to u_cmdb_ci_ibm_cluster
3. Change the identification rule to rely on the name attribute
4. Check to see if the information is shown correctly on the right pane

If name is not sufficiently unique for this kind of cluster, cluster_id may be brought back, but then the probe/sensor must populate this field.