There does seem to be a difference between 5.1.2 and 5.1.1 - see the screenshot I have provided below (might need to zoom in) the related images in 5.1.2 seem to be missing - as we are not the developers of any of the operators in the redhat-operator-index .

Steps to reproduce: 

1. Get a latest version of oc-mirror, e.g for 4.18.x, e.g. version GitVersion:"4.18.0-202505071137.p0.g6b0882e.assembly.stream.el9-6b0882e
2. create an ImageSetConfiguration:

apiVersion: mirror.openshift.io/v2alpha1
kind: ImageSetConfiguration
mirror:
operators:

• catalog: registry.redhat.io/redhat/redhat-operator-index:v4.18
  targetCatalog: jgeo-fi-redhat-operator-index
  packages:
• name: cluster-kube-descheduler-operator
  channels:
• name: stable
  maxVersion: 5.1.2
  minVersion: 5.1.2

3. Do a dry-run
$ oc-mirror --v2 -c isc-v2.yaml --workspace file://. docker://$YOURLOCALREGISTRY/ocmirrortest418-v2 --dry-run