web app – Web survey tool for mediation that reports only whether responses are unanimous

I need a web-based survey instrument for a mediation process with the following attributes:

  1. Users enter categorical responses to one or more questions anonymously

  2. Users can see only whether responses to each question were
    (a) unanimous (all users entered the same response for a given question) or
    (b) not unanimous (the users collectively selected two or more options for a given question)

I cannot find an existing tool with attribute (2): standard web survey instruments (e.g., Google, Qualtrics, SurveyMonkey) all seem to report breakdowns of responses (e.g., 80% yes / 20% no), which is not acceptable for this application, in which users should see only that answers were not unanimous.

Happy for recommendations for an existing or custom solution.