I have been using Cisco Meraki for my MDM and it has been working great. I just bought a bunch of new iPads and am setting up DEP for the first time. I have done all the steps required: Added the order to my Apple DEP account, pushed them to my Cisco Meraki MDM and assigned settings.
Now on the iPad during initial setup I get to a step that says that my organization is going to automatically setup this iPad (which is good). The next step asks for credentials in a Username and Password. I have tried my organization ones, my MDM ones but do not know what this password would be for.
Watching this YouTube video, the iPad here does not have this step. I have done everything the same in this video.
EDIT: Adding some photos from the iPad setup:
After "Setup iPad as New iPad"
The blanked out bits are my organization name.