Precision 7550, WD19DCS USB C not working

I have a brand new Dell Precision 7550 which I connect to my components via the dual USB-C on my WD19DCS dock. Several weeks ago I wrote about an issue I was having in which I could not get the laptop to reconnect to my monitors after it had gone to sleep without unplugging and re-plugging the USB-C cords in. Although clicking with my mouse would wake the laptop, it would not display on the monitors. I still haven't heard from anyone about this.

Well, this worried me at  the time because the entire point of the dock was not to be constantly plugging in and unplugging components. Now, the rear USB-C port is not connecting with the cord. One cord lights up, the other does not. My laptop is giving me a warning every time I turn it on now that it is plugged in to a charger that isn't powerful enough for it to perform at a high level, whereas this didn't happen when both cords would connect.

Interestingly, when I got a different USB C cable and plugged that in to one of my devices, the computer recognized it. This makes me think it is an issue with my brand new WD19DCS dock. What can I do here? Is there a way to replace just the cables without replacing the entire dock?