Can Pin's follow paths?

Puppet pins have position properties based on comp space. If you hold down Control + F4 (on a Max - something else in Windows that I don't remember) you can open up the Parent & Link column. You can also open it up manually from the top bar of the Timeline panel if you right-click in the correct place. When that panel is open there's a pickwhip that. you can drag from any puppet pin position property, easily found by pressing the U key, and the position property of a null.

You can copy a vector path or use the Create Nulls From Paths.jsx script to make the null follow a vector path. That should solve your problem.

You can also create a vector path on any layer, select that path, set a keyframe, cut that path keyframe, then select the keyframe on a puppet pin and paste. As long as the layer that had not been moved, scaled, or rotated, the motion of the Puppet Pin will exactly follow the motion path.

You can also open the layer with Puppet Pin applied in the Layer Panel if it is not a shape layer, and select Puppet from the Render Options and see and edit the motion path of any selected puppet pin using the Pen tool or the Selection tool. You just have to have show all keyframes turned on the Preferences/Display.