All the reporters that wrote news article about the issue said that the demands was from the
Ecuadorian Embassy, not from Assange. A Swedish prosecutor interrogating on
Ecuadorian land has to follow what ever requirement that the diplomats want and those requirements depend on relations and politics. Recently there was a story on Swedish nation TV about a case where the other nation dragged their feet by loosing documents, by demanding them to be first faxed then signed then signed with the right colored inc, then mailed by post, then signed again, and a half year later had past and nothing had happened until an "agreement" was reached on a total different political subject and everything suddenly started to move.
In the Assange case I recall even the prosecutor saying that the kind of things was common when doing police work over borders, but that they hoped that things would be done on time. From what I remembered, it was also mostly on time.