MB03 is not designed to read from the archive, it only reads from the online tables, hence it does not find an archived document.
It is just used as a service function to display the archived data in case you double click an archived document in MB51, but here MB51 had already read the archive, and MB03 just displays those data.
You can implement a modification to make it possible, read Note 431689 - MB03: Display of archived documents