Not being able to create tasks in 2Do using the workflow generously created and posted by @Caleb G finally drove me crazy enough to hunt down fix.
What I found is that, in 2Do 2.x and above, the URL scheme has changed. Updating the original workflow is trivial and and has allowed me to once again create tasks from Alfred.
I did a 2 minute video showing the steps which is available here: https://vimeo.com/167191672
If you are following along, the line you want to copy and paste is:
twodo://x-callback-url/add?task=
Retrieved from the documentation here: http://2doapp.com/kb/article/url-scheme-supported-by-2do-for-apps-like-launch-center-pro.html