This is where having two presenters that are not trained journalists lets them down.
Kate's early days in TV were spent reporting for ITV regional news so I'm not sure that assessment applies here.
I think the bigger problem with particular incident was probably the summary that was provided to the presenters by the production team. If they had been handed the note and been told "this is a summary of the key points of the report" for example, I would wager that they would just trust that what they had been told by those who produced the notes was correct.
As for the presenters' treatment of Sturgeon, it sounds (judging by the Scotsman report) pretty similar to how most political interviews go these days. If what Ben was stating was true, there wouldn't have been an issue to most people in how she was treated, but I don't think it's really his fault he wasn't provided the correct brief (and I doubt any other GMB presenter does their own in-depth research either).