"Because of Hain's premature intervention we shall never know."

Perhaps you'd care to explain how that follows.

He spoke out while a temporary injunction was in force meaning the court has not had a chance to decide the issue/s
Hains has rather destroyed their perogative by premature exposure. Had he waited until the court decided they may have ruled in favour of the telegraph.
But then he would have lost his chance to grandstand.

There's a damn sight more evidence against Green that they has ever been against the Labour Party yet it never stopped you people waging your war against them

Once again you use bluster, rumour, hearsay and opinion as opposed to a court judgement that could establish the facts. I merely highlight the fact that the Labour party has created many NDAs (whether for innocent or nefarious purposed we shall never know)

Please show me the rules in question and apprise me as to who with parliamentary authority has decided that he acted contrary to them.

The matter was subjudice. The rules concerning matters under subjudice in both houses can be fully addressed only at the discretion of the respective speakers. Sub Judice only applies to both houses. Outside the house revised contempt of court rules apply.

Whether parliamentary privilege still applies to matters under subjudice has not as yet been tested(but I cannot be certain on this point) As I have said previously when this situation last occurred the courts decision had been finalised, which even you must admit is a somewhat different proposition to where we now find ourselves.
Many in the judiciary and executive are unhappy with Hains and I imagine the legal beagles acting for the Telegraph are incandescent.
It is early days to know what if anything will happen.

The problem that we have, and I think few would dispute it, is that the law as it stands is in dire need of revision. Judges cannot change the law, they only interpret it. Parliament must make any revisions.
Had the court case been allowed to continue without hains premature intervention clarity might have resulted from the resultant judgement.

As to who polices them:
https://www.parliament.uk/business/lords/whos-in-the-house-of-lords/house-of-lords-members-conduct/

In essence using parliamentary privilege is controversial at the best of times.
It remains to be seen if breaching subjudice rules is regarded as use or misuse of parliamentary privilege.