failed to get install config for cluster: Failed to cast mirror key to toml Tree.

Issue

We are trying to install a hybrid OpenShift cluster using an Infrastructure environment in a disconnected environment.
The cluster installation is starting and then resuming to preparing to install in a loop.
The logs endpoints don't work but I've received the following event "Failed to prepare the installation due to an unexpected error:
failed to get install config for cluster: Failed to cast mirror key to toml Tree.

We followed the instructions of setting up Infrastructure environment and combined the prerequisites from the disconnected guide
https://access.redhat.com/documentation/en-us/red_hat_advanced_cluster_management_for_kubernetes/2.4/html/clusters/managing-your-clusters#creating-an-infrastructure-environment

https://access.redhat.com/documentation/en-us/openshift_container_platform/4.9/html/scalability_and_performance/ztp-deploying-disconnected#ztp-acm-preparing-to-install-disconnected-acm_ztp-deploying-disconnected