I very much doubt that. 
If the layout you seek is important to you, why not build your own notifiers from existing components: HVA,Button,Label, and hide/show arrangements to display/hide your custom notifier, and set button actions accordingly.
For example (using your values for the choose dialog):
All done using \n to create new lines
Yes, this is an option. As I wrote earlier, I will consider pros and cons. From the point of design purposes, using the system notification as a popup over the shaded content of the screen looks better in my opinion.
I still don’t understand though why \n does not work in the text part. I guess this is how the system notification works on Android and iOS.