The only way to achieve that I can think of is to add a temporary node over the container's caption to serve as an obstacle for the link routing algorithm. If you are routing the links as a one-time initialization step, you could remove the obstacle nodes afterwards. If you need the titles to remain obstacles for auto-routed links, you could use the AttachTo method to attach a Transparent or invisible ShapeNode to the container keeping it just over the title area.

Anyway, I think you will find the current one-segment link looks better than if it was making four additional bends to avoid container's title.

You might also consider left or right -aligning the caption text via the CaptionFormat property; this should move the caption away from the link, at least in that example.