MDM configuration profile payloads and their values are derived from Apple. It's best to know what payloads Apple has prescribed first then determine if you the MDM product you've chosen(Jamf School, or Jamf as many annoyingly refer to all of their products as) has implemented them. In this case App Lock doesn't have a passcode Setting as shown here.
Beyond Jamf Parent I don't know of any other way to achieve this for those that don't have access to the dashboard to temporarily remove that config profile. If the app is just loading web based content like an LMS for instance then a kiosk app like Moki Kiosk has the ability to trigger single app mode on and off.
