They have a lot more power than you might think from that quote.

https://en.wikipedia.org/wiki/National_Labor_Relations_Board...

They can now try Apple in an administrative court, with an 'administrative judge' selected by the agency, then get a (normal) Article 3 court to rubber-stamp their 'order'.

Not a lawyer here. Why does an Article III judge need to get involved, and not in other administrative matters, like say, in an administrative immigration case?

edit: further investigation has indicated that it's immigration law which deviates from usual practice of administrative law, which would potentially expect an automatic stay in a context like this.

To the contrary, the order already exists (“stop it”) and this article describes the second part of the process you linked to:

  > The decision of the Administrative Law Judge may be reviewed by the five member board

Pure speculation—the doj can use that determination against apple in any future proceedings.

It’s like a GAL report for a family law case; independent investigator provides a report which the court will then use to inform it’s decision.

That's like saying "the police can't hand out sentences, so what's the point of having police?" The NLRB's investigation is part of the process. It can and does cooperate with the DoJ and various other federal agencies and courts.