Allow "If" Variable Statements in API Monitor

The API monitor is great in that you can set a value based on the response. However, I have a use case where I am looking for a value and if that value exists, then I need to set another variable contained in the response. This variable/response ONLY shows up when the response contains a validated value. An example would be hitting an API endpoint for a maintenance page. Most of the time this returns a json value that indicates it is not in maintenance. However, when it is in maintenance, a date, who placed it in maintenance, and unique ID is returned. I would need to capture that for later actions and escalation.