I should note that I have no idea why this worked, but it did.
I made a partition in my computer's memory. Then I installed a separate version of OSX. When I booted to that partition the Robin connected flawlessly. I thought that it would only work in the partition I created, however, when I booted back to the default partition, the Robin connected.
For perspective, here is a list of the things I tried before I got it to work:
- Fast booting the Robin.
- Rebooting the Robin.
- Wiping the cache of the Robin.
- Restarting my computer.
- Clearing the SMC and NVRAM of the computer.
- Turning on usb debugging.
- Switching between usb modes in developer options.
- Probing the usb ports in my computer (software).
- Disconnecting and connecting the usb several times out of pure frustration.
- Connecting the Robin to another computer (it connected).
- Uninstalling Android file transfer and reinstalling it.
Hopefully one of these things will work, if someone has this problem in the future.