Custom Formatting removes natural drill through capability - manual solution needed

Question

There is a need to create custom formatting for an indented Financial Statement with subtotals. This is not out of the box Power BI functionality and to reach a solution, the inherent aggregation and drill down functionality has been stripped from that visualization through the use of a "template" table to create indentions and subtotals. This is connected to the fact table through a "virtual" connection via a switch function. The formatting is as needed but there is still a need for drill downs.

A proposed solution I’ve been explored is to use an if condition for when one row is selected. When a single row is selected it would then show different dimensions and measures for the given chart, mimicking a drill down. I'm trying to use an isfiltered condition to create this action but I've had no success thus far. I’m still trying to determine what function would provide that functionality or if there are better options.