The front ir port is working fine with the TSU9600 thru the rfx extender.
With the old TSU7000 and its rf to ir repeater the rear wired ir port on the Anthem worked fine and passed the ir codes on to 4 different pieces of gear without issue (3 Sony DVD carousels and 1 Denon DVD player).

The only difference is that with the TSU9600 I'm using the stock ir codes from the Philips database for the Anthem & Denon, not the ones recorded directly from the remotes that I had to use with the TSU7000. I'm using ir codes for the Sony carousels recorded directly into the TSU9600.

All codes for all gear work fine coming out of the RFX9600 going directly to each piece of gear. In fact, I found an old Xenix ir expander from a project, that I wired via 3.5mm to 3.5mm to the RFX9600 that is working fine sending signals to the 3 Sonys and the Denon.
It's just the rear wired ir input of the Anthem that won't see ir output from the RFX9600 and pass it along. Very odd.