Well. Section 47 is a real delight, a diabolical inversion of the principle of locus standi. Increasingly, there are agencies and laws which say that "you cannot take us to court". As though writing it makes it somehow legal. Reminds me of calvinball.
This has nothing to do with sovereign immunity. It is just an act. Expectedly, it was struck down by the Supreme Court as unconstitutional. It was just a ludicrous thing to try in the first place.