Hi Markus
Can't answer the vibration question as I've never piggybacked.
Rho has all the nebula types pretty much so you'll encounter the same issues DSLR users have for all reflection nebula... You can counter this by upping the total integration time (a LOT) or just accept it as a cost of using a DSLR. For the reflection nebula, few globs and dark nebula, your DSLR will be absolutely fine.
Here's an example of the 5D IV on Rho. There's a definite lack of red emission nebula detail.
https://www.astrobin.com/412926/?ima...gr&user_page=2
vs an image (my own) of Rho with an astro camera.
https://adamlawler.smugmug.com/Astro...ts/i-2mw5rdG/A
I have the same camera in my Canon collection and it's pretty good but be aware of issues with calibration files. Bias files on this camera can actually make sensor banding worse. I would suggest taking a whole gamut of calibration files (darks, flats, dark flats and biases) and then pick and choose the right combination when you edit.
Good luck
edit: just another 5D IV example here, with the same lens I used for my image. There's a difference!
https://www.astrobin.com/406736/0/?mod=solved