No, this is not possible. But you can use multiple detail views (Workshop High Resolution Image (pixel-based), Workshop
Technical Illustration (vector-based))
If you need this for a video, render your "digger"-videos in another videofile and use something like
Adobe After Effects to layer one video on top of another.
You can't get two interactive diggers in a Composer project. That's an ER documented in SPR 483692 - Ability to use multiple Digger tools simultaneously.
However, you can capture Digger content as a 2D panel and keep moving on. I use that trick a lot.
You can capture images with the digger, but you have no control over the quality. It is more like a screenshot
of your view/actual scene. With the method via the workshops Technical Illustration / High Resolution Image you can control
the resolution, DPI etc. And you can update your detail views very easy. So I would try the different tipps and see what fits best
for your workflow!
Best regards, Phil