I am working on reproducing the use cases from the DMN Method and Style book, and while following their methodology was unable to create the same behavior documented from Trisotech tooling, the so called "Decisions first". In this methodology the practitioner starts from the DRD definition of decisions, inputs and types; and then follows to create the decision tables and calculations from top to bottom.
While creating the decision table that requires an input and a defined output of a "supporting decision", the decision table generated when selecting the expression type of the decision comes with no reference to the required supported decision.
More clarity in this mojo: https://mojo.redhat.com/docs/DOC-1215621#jive_content_id_DRD_Supporting_decisions
and in the steps to reproduce.

Acceptance criteria

• Create a new DMN model
• Add an InputData
• Add a Decision, called A
• Add another Decision, called B
• Link the InputData to A
• Link the B to A
• Edit A and set its expression to DecisionTable
• It should have input columns for the InputData and B.
• You should be able to use built in types and custom types (including structures).