Is there a way to change the owner of a dashboard? Or can we have more than one owner of a dashboard?
There can only be one owner of a board. The sharing settings in Kanbanchi are provided by Google Drive and it does not allow more than one owner.
Personal users (gmail.com) cannot pass ownership of the board to other users (unlike with Docs and Sheets). However, within G Suite domain, G Suite Admin can move ownership of all files, including Kanbanchi boards, to other members of the organisation.
A quick workaround would be to share the board with a colleague, who you want to see as the owner. Then she must сopy your dashboard into her Google Drive, thus becoming the owner of this copied board.
All settings will be copied, excluding comments, sharing settings, notifications and dates in Google Calendar. Permissions of attached files also must be checked, because original files belong to you and are placed in your Google Drive.