If a build has no changelog history (i.e., the change log looks like changelog-empty.xml), then the "More change log history" link isn't shown because the build itself it not shown.
When the first history is copied over, you might check to see if the change log is empty for the build and put this dummy changelog.xml file there. It's not pretty, but it works and reveals the "hidden" data.
|Field||Original Value||New Value|
|Summary||More Change Log History link is not shown for builds which had no history originally||More history link is not shown for builds which had no history originally|
|Workflow||JNJira [ 141626 ]||JNJira + In-Review [ 175516 ]|