How can I tell if the digitizer I bought was faulty?

The touch digitizer on my Pixel 2 XL broke, and because I have a security-focused OS (CalyxOS) on it that doesn't allow new devices to connect without permission, I cannot access it with any input devices to rescue my data except a new touch digitizer.

I purchased a touch digitizer from Amazon and it does not seem to work, although the display does. I am willing to get a refund and purchase an OEM part, but I want to make sure I am not barking up the wrong tree.

Is there a way to test the pins on the motherboard with a multimeter or another cheap piece of equipment? Or maybe another diagnostic technique?

Lastly, if it is an issue with the motherboard, how would I be able to get my data?