Allegedly, on or about 18 May 2017, William sent:
Yesterday evening, a third IT grad student (PhD candidate specializing in cloud computing) came to help with this problem. After I showed him the log file and the discussion in this list, we booted, and of course it failed and dropped us into the dracut shell. He examined the rdsosreport.txt file. He ran "fdisk", but he typed too fast for me to see the whole command line. He responded 'y' to a few things, but it was too fast for me to see what...
Well, my advice would be: To see him again, mention that things are going well now, ask him what he had to do, take notes.