We don’t have specific documentation saying that we support that particular registry, but in some registries that do not support a “Create repo on push” feature, it’s necessary to make sure the repo names exist before pushing images into them.
If you’re using the airgap method kubectl kots push-images to push the images to the registry, try making sure that the repos exist first.
Here’s a related Community article for making sure the images get pushed into a private registry before installation: How can I separate the "push images" and "deploy" steps of installing an application using Replicated?