This is published in `1806 Das Preussische Offizierkorps und die Untersuchung der Kriegsereignisse` issued by the Grossen Generalstab by ES Mittler, Berlin 1806.
But that source does not contain the personal quotes by Sergeant N..., nor does it mention any conversation with an officer of fusiliers.
Digby:
Yes, the passage is describing the same movement of Grawert's Division covered in Marwitz's report, but as you say, it does not include the same details. I doubt that Marwitz would quote a regimental officer's innocuous account of his personal experience, even if Marwitz had it available to him at the time.
Best Regards,
Bill