Dynamic Dependency with Template Repeaters

Working on a Vision Window. I've got Template Repeater 1 (TR1) with Toggle Buttons as the template.

Currently, TR1's template parameters is bound to a RunScript() expression that returns all child folders to the default tag provider. Each TB template represents a folder.

I'd like to have all folders whose TB is set to On/True have their child folders then displayed in Template Repeater 2.

I know with the use of a button as a manual "data refresh" I can make this happen. So I could probably use similar events that feel less "manual" to achieve the desired results - but I was really hoping for something that felt less like a workaround - any ideas?