Note that the new "split" moodle-ci-runner already supports this:
https://github.com/moodlehq/moodle-ci-runner/commit/9c4e671d3ece4462e96723a264d4841d6eeb239d
And we have been running it @ the "MMP403.02.02" jobs @ CI, that require a couple of CFG settings to be configured.
Covered with tests, really simple stuff.