In 8.4.3, the survey smart shape does not route the survey questions to the current user, even when the step is correctly routed to “current user.” When a user runs the flow, the flow stops right before the survey, and the user receives two notices and options to advance the flow manually: "Wait: awaiting dependency to be fulfilled" and another one with an icon for another user that says "Question page: task in survey name."

Solution:

1. Open the process in Dev Studio.  
2. View the flow. Select Open process in upper right corner, above the flow.
3. Right-click on the shape, then select View properties.
4. In the Route to dropdown, change routing from Current user to Specific user.
5. Enter pxRequestor.pxUserIdentifier in the Operator field.

You’re good to go!

DISCLAIMER: I can't take credit for this solution - but I hope it's useful.