Trigger an automated outbound message on a different object than the DocGen Package starting object.
In the Drawloop_Next Field, add the additional parameter objectype:DDPstartingobjectAPI
Example:
If the Drawloop_Next field is a formula field - enclose in quotes as needed for formula validation.
Automated DocGen Packages: https://help.nintex.com/en-US/docgen/docservices/#docgen-sfdc/Services/manageDDP/AutomatedDDPs.htm?