Pipo Don't know what else I can do to convince you that this isn't GrapheneOS rather than to explain that I know for a fact this is not possible on GrapheneOS.
It seems like someone forked GrapheneOS and added that. The code is open source, they can do that.
Them "saying" it's GrapheneOS doesn't make it that. A fork of GrapheneOS is no longer GrapheneOS. They likely meant that whatever they made is based on GrapheneOS. If they're marketing or portraying that end product as GrapheneOS, that's incorrect and they shouldn't be doing that since it leads to these exact confusions.
By the way, that wipe feature on that fork likely doesn't work correctly, same with apps like Wasted. GrapheneOS' duress feature will wipe without rebooting the device, therefore preventing situations where the wipe can be cancelled.