Rollback Not Working As Expected (3.0.1)

So, back for more fun! I am trying something relatively simple; inserting data into multiple database tables, via FK relationships. Per the documentation, the Rollback option being specified in the URL

?rollback=true

should make it so that any failure to insert data in one or more related tables would ensure that everything rolled back. Yet, putting bad data that cannot insert into any of the related tables still results in the Parent table and potentially other Child tables being written to, regardless of the Transaction purportedly being rolled back.

Does anyone have a solution to get an ACTUAL rollback to occur, outside of resorting to using only Stored Procedures for everything? I am really beginning to have some major regrets at using this platform :angry:

NOTE: This “works” the same both with a translation pre-process script and with avoiding the pre-process script (ie, directly specifying the data for each table/relationship) – so the pre-process script is not the issue.