Passing a screen_name to Dukt Twitter
Accomplished this by setting the get request url, then passing it into tweets:

{% set handle = entry.twitterHandle %}
{% set url = 'statuses/user_timeline.json?screen_name=' ~ handle ~ '&amp;count=3&amp;exclude_replies=true' %}
{% set tweets = craft.twitter.get(url) %}


Hope this helps someone else. Thx!