Rhythmic clicking sound during light braking?

Hello, that definitely sounds like the ABS module pulsing one of the solenoids, I would have the ABS module scanned for codes, along with having all 4-wheel speed sensors monitored with a scan tool to see if there is one sensor reading differently from the others. You will need a scan tool that can scan all the modules in the vehicle, not just the engine computer. If you don't have a capable scan tool, you can take it to a shop and have them at least diagnose the issue, write all the information down, and we can help you with replacing a speed sensor or check the wiring, if that's what is going on here. I'll take a look through service info on the ABS system for this vehicle as well.

Do a visual inspection of all 4-wheel speed sensors, make sure there are no damaged wires or issues with the sensor connectors.

So I did come across a technical service bulletin (TSB) about the dealership adding an additional "Friction Disc" to the wheel hub due to a noise (diagrams 1-4), and then a Recall about a limited amount of vehicles being built with an incompatible wheel and brake/suspension package, but this only looks to apply to 173 vehicles, so very unlikely this has anything to do with your vehicle, but just wanted to put the information up. The TSB though might be worth looking into if there are no ABS or traction control codes stored, and no issues found. A scan tool should be able to show under live ABS data if the ABS module is applying one or more of the hydraulic solenoids. Possibly also showing if the module is receiving data to do so from a bad sensor or if something else is going on with a sensor such as something effecting the sensor.
I'm going to post some other additional information next that will be helpful.

This the ABS and ABS module operations, check out diagram 4, it explains Premature ABS cycling/application with what can cause it to happen, which is what it sounds like you're dealing with. Let us know what you find and what the repair ends up being, it will help others who run into this issue. Thanks, and I hope this service info helps.

Vibration sounds like this can be very difficult to diagnose, but I did find some case studies where, being that this is rear wheel drive, that noise is very close to a failing drive shaft bearing (carrier bearing). It seems they go out at even lower mileage than you have, it's the closest sound I could come up with after some research. It's best to have a dealership take a look at it, because it appears to be a common failure point, and they might hear that and know what it is right away. Whereas a small private shop might not be as familiar with these vehicles and end up replacing parts that do not need to be done. But it's good that you did rule out the ABS yourself, I think that was a good call on your part, because it did sound like an ABS solenoid activating. Let us know what the outcome is, it will help others in the future. I hope for the best and thank you.

Interesting, there was enough play in it to move, looks like it's a high failure point, hopefully that will take care of everything, there is some service information on replacement, do you have this type of bolt on driveshaft setup? This is just the installation info for a driveshaft that bolts onto a flange at each end.