This is a BUG in the framework, 

Is there a way to fix this bug?

Yes, we provided a hot fix from the product, ideally the issue has to be fixed from the framework. the case id was CS0272989

@UncheckedAccess

FUNCTION Get_Op_Desc_By_Bom_Type_Db (

   contract_         IN VARCHAR2,

   part_no_          IN VARCHAR2,

   routing_revision_ IN VARCHAR2,

   bom_type_db_      IN VARCHAR2,

   alternative_no_   IN VARCHAR2,

   operation_no_     IN NUMBER ) RETURN VARCHAR2

IS

   temp_ ROUTING_OPERATION_TAB.operation_description%TYPE;

BEGIN  

   temp_ := Get_Operation_Description(contract_,

                                      part_no_,

                                      routing_revision_ ,

                                      Shop_Ord_Code_API.Decode(bom_type_db_),

                                      alternative_no_,

                                      operation_no_);

   IF temp_ IS NULL THEN

      temp_ := Language_SYS.Translate_Constant(lu_name_, 'OPREMOVED: *** OPERATION REMOVED ***', Language_Sys.Get_Language);

   END IF;

   RETURN temp_;

END Get_Op_Desc_By_Bom_Type_Db; 

Add this new method which now accepts the bom_type_db_  to the RoutingOperation.plsql file.

Then Refresh Server Cache. (Object Connection Cache).

Restart the application.

Then in Object Connections window, when creating a new object connection for RoutingOperation you can set this new method as its method name.

Object description will be fetched as expected when this method is used.