I would add it on a North Arrow Layer in my Plan View and then make sure that the North Arrow Layer(s) are part of the View Filter applied to the Dynaview or Dynaview Collection in the Sheet View.
If you want to draw it in the Sheet View you will need to either Align it to a Grid that you have applied to the Dynaview or you will need to know the rotation of the sheet created by the Dynaview or Dynaview collection and use that to orientate your North Arrow Block. If you have multiple Sheets, then you will need to pick a suitable location for the North Arrow in each Sheet Area (defined by the Dynaview or Dynaview Collection) for the placement of your North Arrow.
Does this answer the question?
Since a single sheet can incorporate multiple Dynaviews, and because each Dynaview can have its own orientation, you really need to tie the North Arrows to the Plans.
If you are using the Plan and Profile View Sheets, then the North Arrow can be placed automatically in those types of Sheets but not for normal Plan Sheets (at least at this time)
Alan