MAX BR1 IP67 8.1.1 External portal fails on redirect back to device

Using the example PHP downloaded here: Configuring an External Splash Page for Captive Portal

I was able to set up a page and SSL for the “hostname” element of the captive portal setup, and I was redirected to it properly upon connecting to the SSID. Upon clicking “agree” on the external portal, however, it times out trying to reach I am not sure what to change about this URL, as I am not sure where to look for the replacement for “device”.