Is the arc you are trying to dimension being deformed by the flat pattern? If so, it is no longer a true arc and cannot maintain the appropriate center.
However, you do have the option to have extruded arcs generate an axis, and this may resolve the axis following the flat pattern state.
Unfortunately, the config.pro toggle for this does not affect already created features.
A work around is to place a hole in the center of the arc and see if it will follow the flat pattern but this might generate "intent" errors unless you actually remove some material.