Identify API is not called at all when "any" finger is used as option in verify
https://gitlab.freedesktop.org/libfprint/fprintd/-/blob/master/utils/verify.c#L103
Due to this condition, finger_name = g_strdup (fingers[0]);
will always have a value.
But in the API in device.c static void fprint_device_verify_start(FprintDevice *rdev, const char *finger_name, DBusGMethodInvocation *context)
the Identify API will never be called at all since finger_num will never be -1. https://gitlab.freedesktop.org/libfprint/fprintd/-/blob/master/src/device.c#L863