Is there a way to find the IMEI on a Pixel with a completely damaged screen?
Yes you can find IMEI of your damaged Pixel Device or any Android device if you have or had your google account logged in .

Check Google My Devices
or alternatively logon to Google Find my devices @ https://www.google.com/android/find

on your device list click the ( i ) information icon, you can see your device IMEI.

Hope this helps.