I suspect the easiest thing to do is to run the install-on-cluster command in the Dockerfile that you use to generate the Docker image for your master pod.
To initialize Hail, I would just use hl.init(master='spark://...') If you need to pass special spark configuration, you can use spark_conf=.... You don’t need to set the class paths, the serializer, or the Kryo registration if you let hl.init create its own SparkContext.