Migrating from Ambari to Cloudera Manager can leave the Ambari-managed HDP artifacts and links that may not have changed. After everything has been configured, go through each of the services and deploy Client Configuration. This fixes any missing configuration references in the cluster.
Ensure that the etc/hadoop/conf link points to the correct platform. Cloudera Manager and Ambari store binaries in different locations. You might encounter some issues if the link is pointing to the older location.