Level Streaming 'Set Should Be Loaded' only works in PIE?

I have an array of sublevels to load when the persistent level loads… the combination of which depends on where the player will spawn. Rather than using the Open Stream Level function (which can’t be used in a ForLoop because of the Open Stream Level function won’t rerun until previous loads are complete). So, following the topic below, they suggested using the ‘Set Should Be Loaded’ and ‘Set Should Be Visible’ bools in the level streaming object and it works perfectly, but only in PIE mode, not in Standalone or Packaged build. Has anyone else encountered this? Am I misunderstanding something?