Problematic for whom? You seem more concerned about this than the Swedish prosecutors. It seems this was the procedure they agreed to. Whether it's normal or not I don't know. But they haven't made a fuss about it. And I think they would have if it was a big concern.

They could ask for a second interview and present follow up questions.

But this raise a primary question. Is the distinction of being able to instantly make follow up questions of such importance that it will swing the binary choice of charging Assange of a crime or dropping the case?

The primary cause for a guilty and not guilty verdict should not be the quality of the environment for a police interview. Not for a such serious allegation like this.