In many organisations, a break in a system holding production data is serious even if it isn't a serious break, so being able to roll back or otherwise undo would not cut it.

Much better would be to give them a replica to work on and a change confirmation process that allows signed-off changes to be pushed into production.

As another idea, since all the changes are described in an AST, I could offer a "undo" in the query log for INSERT action. The UPDATE action would require a bit more work as I don't track the previous data (and it could be changed in another system as well).