Well, we got a bunch of new computers to replace some of our old ones, and it’s got to the point where we don’t really want to manually run Pre-provisioning on 250+ computers, does anyone have an idea how we could run a White Gloves Autopilot Unattended Pre-provisioning while we already have HWID for all those computers imported in intune?
I think you’re confused with the terms. White Glove and Autopilot.
I have no idea what scenario you want to use but I’m guessing you’re going for a user enroll? With that I mean, you provide the computer (laptop or desktop) and then let the people log-in and let them run to the autopilot process (AAD login, Windows Hello, stuff like that).
If you have the hardware hashes and you imported them in intune. I would just make a dynamic group targetting those devices (or use a group you already have) and link it to the autopilot profile you set-up with the options you want. You can enable White Glove here but unless they are in a no-internet zone or a very slow internet speed zone I would not bother with White Glove because then you need to boot all 250 devices press windows key 5 times and let it run.
That’s the very short answer tbh 
We use white gloves profile, but before user is signing on we run pre provisioning so that user doesn’t have to wait for 10-30 minutes while the computer finishes autopilot provisioning.
After Autopilot has set up the device to comply with company policies the user can just log in and basically run through AAD login and windows hello, obviously after user logs in there are still some things that need to be done, so it usually takes 10-15 minutes to sync policies and install predetermined software.
The setup can’t run without internet and the aim of white gloves pre-provisioning here is to decrease the time needed for initial setup and overall white gloves here is not the issue, the issue is that we need to hit win key 5 times for each computer and hit tab and enter twice 
there really is no reason why anyone should be sitting at these computers to manually launch provisioning, there probably is a way to just force it to run after win boots up with MDT or something like that, the question is how.