This is what I had sent our Canvas rep but forgot to post back to this thread. I spun up 7 test sections and did a full course copy to see if I could break these again and this is what I discovered.
New Quizzes will show an error message with retry prompt when it is actually still processing the copy operation. The screenshot below is from the Assignments page after the import. The objects initially appeared with a blue spinning loading wheel indicating they were still copying. After ~15 minutes you can see this error was produced:

If you see this error after a New Quizzes import, then it is most likely still processing the copy operation even though there is nothing to indicate this. Check back in 1-2 hours to see if the New Quizzes item has completed the copy operation. The other bug is that when the New Quizzes item finally imports it will come in as unpublished, which is just something we train our teachers to do in their own sections.
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