I was reading this answer about different methods of getting the last identity value entered into a database.
From what I understand,
<cfquery name="queryInsertA" datasource="source">
INSERT INTO tableA (columnName) VALUES (value)
<cfquery name="queryInsertB" datasource="source">
INSERT INTO tableB (fkey_tableA, columnName) VALUES (@@IDENTITY, value)
The answer you linked already explains what the main issue is with
@@IDENTITY: scope. If your insert triggers another insert, you get an unexpected identity back. Transactions do not change anything.