The troubleshooting guide at https://access.redhat.com/documentation/en-us/red_hat_3scale_api_management/2.13/html-single/operating_3scale/index#troubleshooting-the-api-infrastructure
needs updating

For example there's no mention of
$ oc adm must-gather --image=quay.io/3scale/must-gather

or using

$ oc adm must-gather

to get additional information about the cluster (not specific to 3scale):