I might not be able to answer your question completelly, but if I look Kiosk mode management in Intune, I see it supports only Microsoft products. Not sure, are GPOs different for this versus Intune. You also should change your tag, or at least add Windows 10 tag, because Kiosk is client OS function.
Applocker is very different approach to Kiosk mode I think. With Kiosk mode, you really limit usage of the Windows Desktop and force specific app or apps, and deny everything else. Applocker is security monitoring and deny feature to launch any suspicion apps which is not included inside %programfiles% and %windows% by default. I see why you consider applocker for this, but as I understand, controlling Kiosk scenario with applocker would be hell.