RuboCop 0.66.0 has trouble with this piece of code

rubocop.md

In This PR, I disabled a rule inline.

module Gemstash
  # Storage for application-wide variables and configuration.
  class Env
    module Helper
    # RuboCop 0.66.0 can not decide where to put that "private"

    private # rubocop:disable Layout/IndentationWidth

      def gemstash_env
        Gemstash::Env.current
      end
    end
  end
end

Is there a way to format this, without breaking any of the rules?