if you (or someone else) is still looking for a solution, there is a workarround:
- use a drawing style for some small single part (for example);
- delete the view from the drawing and save it. Now the drawing is empty, but it gets de-registered from the model
- register the drawing again in the model
- It is displayed in the document manager, the only drawback is that it is under "Project documents - Details - Unknown".
I don't know if it is good enough for you, but I need to reserve the few pages that shouldn't have any drawings and this does the trick.
Before I saw your post and tried the described method, I would just move the generated view outside the plot area - it was there, but will not show on the generated PDF...