I just assigned my first Kami assignment through Google Classroom today. Every student in all 6 of my courses has their own copy except one student. The Kami extension was added by our IT department so I know the student has it.
They were logged in with the correct email as well. I even tried assigning two more times to just that one student and an attachment still wouldn’t show. When she clicked the “Open with Kami” link it just opened her Google Drive within Kami.
I don’t think it ever made an attachment from the beginning too because there weren’t any in my drive under her name.