You want to find out which IGH can support the Ultra Torque and power, then choose the one with the widest gear range.
The one we know works, is the Rohloff, Very rugged, best 526% gear range, but it is very expensive and has more gears than really needed (14).
Next in line to test would be the Alfine 8 as suggested (307% gear range), and if that is not strong enough, may be the Sturmey archer 5 (243% gear range) also mentioned in an earlier thread.
Finally there is the Upcoming NuVinci N380X (not the existing N380) with a 380% gear range. On paper it is not supposed to handle the 160Nm of the Ultra, but it may.
As a main manufacturer, one thing you can do is try to explain to IGH Manufacturer that there is a strong need for IGH for High power electric bikes like the ones using the Ultra motor, to motivate them to develop stronger versions of their IGHs.