Time saver: Sharing files to slack

Amy,

I'm just a newbie to Dropbox-Slack Integration, and trying to get up-to-speed quickly to save myself and my small team from "death-by-ReplyAll-emails-with-file-attachments-for-collaborative-editing"! 

This short video represents the tip of the iceberg relative to that goal.  I am currently engaged in a Q&A with Jay on the subject. Here's a link to that conversation: https://www.dropboxforum.com/t5/Dropbox-installs-integrations/Shared-File-Edit-Access-via-Dropbox-Slack-Integration/m-p/585155#M118886 

I don't want to "cross streams" with that conversation, but here is a related question:

• With my Dropbox account already linked to my Slack Workspace, I created a new [private] channel in the Workspace. However, that newly created channel does not appear in the Slack channel list when sharing a file from Dropbox to Slack. In other words, I only see the channels that existed at the time I initially linked my Dropbox and Slack accounts.
• How do I resolve this?