We don't know what ISE is requiring on their side so there is no way for us to tell you what you need to set in the controller. You can take a look at the how to docs for Clearpass but we use a different redirect than ISE. ISE hijacks your DNS and again you need to work with the NAC vendor and I'm sure they have a how to doc on setting up with other vendors. They now claim to work with others so they should have a how to doc just like we do for Clearpass and Cisco WLC/Switches.
Someone on airheads may know but if you need an immediate answer then i would use their forum.