Section 5.4 of the
Magnetic Encoder User Guide describes some ways to do this.
You can solder you own wires to either of these breakouts:
Disclaimer: I have never used these breakouts, so make sure you have someone double check this advice.
The first one is designed to be used the other way around (attaching a non-standard encoder to a Talon SRX), but the manual states that it is okay to use it for your application. You would wire 5V and ground from the roboRIO to the appropriate labelled pads on the breakout, while the A and B pads should be connected to two digital inputs on the roboRIO. Then it can be used in code like any quadrature encoder.
If you use the second breakout, you can do pretty much the same thing, but you have to figure out which pads correspond to the A and B channels of the encoder.
Also, AFAIK, there is no way to use the absolute position mode of the encoder without connecting it to a Talon SRX.