I can not find API that get request lists from other users for approval by the current user.
GET RequestSets API get only current user's own requests.
If the current user is the approver, it need an API that get the list of requests from other users.
Without this, I think, the ‘PUT/Request/Approve or Deny ‘ API cannot be so useful.
If the API that get request lists from other users is developed, then it will enable to make other web program for approver side in PBPS project and make PBPS API Set richer.