Going by the article, Solidarity offered help in May and last week Gordhan accepted the offer and asked Solidarity for a list of people they think would help Eskom.
As Minister of Public Enterprises, he is in charge of all SOEs, so I'm sure he'll probably talk or has already talked to Eskom management and HR and whatever else about this.
That's the whole problem, he cannot be talking to HR or the Management about anything that amounts to undue interference in the operations of Eskom, that's exactly what ministers in the Zuma era did and that's how we ended up with the likes of the Prasa "engineer" and people like Hlaudi.
Pravin is responsible for the board, and the board is responsible for the management and the management is responsible for the operations of Eskom, which includes getting the right people with the right skills.
If it happens that Eskom has an issue where hiring certain people negatively interferes with their AA and EE targets the board can approach Pravin and tell him about it, Pravin can therefore give the go ahead to the board which can liase with management. At no point can it ever be acceptable that the minister is going around making agreements with whoever pertaining to HR matters at Eskom, it is improper.