After purchasing the new DLC pack yesterday i had the same problem.
When i scheduled to move a bear to the habitat, after a while i noticed that the bear wasn't picked from the Trade Center and the staff picking notice kept flashing (normally it only flash once).
Then i goto the Trade Center and saw a Caretaker was jammed outside the Trade Center, standing outside the door and seems cannot move, then i just move the Caretaker and release him to a nearby location, he went normal and picked my bear to the habitat finally.
This seems to be a path-finding issue not related to the path, since the Caretaker could normally reach the building without modifying or repairing the path, maybe there are some mirror changes in the new DLC that affect the path-finding for staff members. If this situation happens often someone shall report it as a bug and let the official to find clues.