I had started that thread, so some feedback. I used nether and this Secondary NS on Hurricane Electric - #6 by davness at the time
I added all listed HE servers in that post to MIAB.
I did not change anything at Gandi. I only have the name servers setup in the way as in the MIAB guide. ns1.box.etc ns2.box.etc
That worked for me. It took about ten minutes to show in the status page.
I hope this helps.