It ought to be possible using the GUID. Here is something I've published before about how to use the GUID for a task to create a shortcut. You could experiment with this approach in OneNote or perhaps someone else can give you an exact method.
CREATING AN EXTERNAL SHORTCUT TO A TASK OR FOLDER
1. Select the task/folder in the outline that you want to link to.
2. Go to Task/Advanced/Properties (or press Control+F12), and copy the "Task ID".
3. Create a shortcut (Right-click in space on the Desktop, select "New", select "Shortcut" and for the "Target" data, use your path to mlo.exe, your MLO data file location, and the Task ID you just copied. For example: -
"C:\Program Files\MyLifeOrganized\mlo.exe" "C:\Path\To\My\To Do File.ml" "-task {C8BFFF49-2A0A-4532-8398-321CC49595FE}"
Remembering to use quotes and spaces where shown.
4. Other switches can be substituted e.g. -zoom
The shortcut created can also be used very effectively in conjunction with a launch program such as Launchy or Slickrun for instant keyword/keyboard access from anywhere in Windows.