Hello Shaun,
Basically what I have been able to collect ...
We were working for a "DISA STIG" version of Gluu Server lately and which brought the work of releasing much security tightened WrenDS ( Free Open source fork of OpenDJ ) and 4.3.0 has that version inside.
One of my colleague, Davin, should have emailed you already for further discussion on that.
But... we do have a blog on that if you are interested: https://gluu.org/installing-gluu-server-on-rhel-8-with-the-disa-stig-security-profile/