TL;DR a modification of an Object (aka Structure) in the Data Model does not get reflected in the DMN Model.

Maybe someone can point out the error in the following scenario.

(1) Using the DMN editor in BC RHPAM.7.9 I defined the "Ve" Object (aka Structure) and the "Ve_data1" simple variable in the Data Model as custom data types

(2) "Ve", named as "Vehicle", was used as data input to a DMN model and a decision was defined backed by a decision table

(3) when the decision table was first created the columns for the "Vehicle" attributes were created as individual columns.

(4) Modified the "Ve" structure by removing some attributes

(5) The deleted attributes are still available in the decision table.

I have two issues in this scenario.

(I1) Step (3). By creating the columns as individual columns of the "Vehicle" variable in the decision table any sense between them belonging to the "Ve" structure is lost. Furthermore the decision table allows for changing the data type of the columns despite the fact that these belong(?) to the "Ve" object.

(I2) Step (5). I was expecting that by modifying the columns in the data structure that change would be visible in the decision table as well. Yes, a warning is generated, but it is cryptic, lost in a table full of equally cryptic messages and no visual indication of the actual problem in the decision table. I can check the messages and find out what is going on, but explaining this to my customer proved to be quite a challenge.
We are still targeting DMN to business analysts I presume.