@Zach_Kaplan Unless Zach has something else to try then here is what I would do.
[Edit]Hum, you did measure the voltages with the connector removed, right?
Ok, there’s something wrong with the electronics. Assuming the connector is still removed. It may be a simple set up issue because the Arduino is supposed to be pulling those pins high with internal resistors.
At this point I would try to reload the grbl software to see if it is just a software issue.
You can do it this way:
https://inventables.desk.com/customer/en/portal/articles/2069033-grbl?b_id=9563
Or this way: