A few weeks later, I was prototyping it out and hooking it up to an Arduino UNO. I had a TLC5916 LED driver chip hooked up and running an 8 bit binary count on the LEDs you can see. If you look at the indicator LED on the receiver board, you can see that something isn't quite right.
Something is generating RF noise in the 60kHz band (which is perfetly acheivable by the components on the board). You can see that, depending on the orientation of the ferrite antenna with respect to the breadboard, the noise comes and goes.
I'm not sure whether this was because of the the long curving wires from the Arduino Uno to the breadboard acting as an antenna; or if it is because of switching noise from the TLC5916 as it drives it's output FETs with the PWM train.
In those infamous scientist words, "More research is required"