I'm another cruel Apple marketing victim. Proved any of your solutions, and anything works for me. I was tired and desperate. I just bought an iTunes Match membership for a year and that solved my problem, but Apple already took its middle finger and showed it to my face and says: "I told ya... No piracy items."
It took me about... How many do think...? Hours? Hum...! It took me FOUR DAYS to upload all my 4,678 songs!. It seemed to be FOREVER!... But after a long time waiting, fighting with my modem, consuming a lot of broadband all items are on the Cloud. Now, I can download all my songs and smart or ordinary playlists into my iPad and iPhone. But it was awful, tedious and uncertain...
Sincerely, don't recommend it, but I depend on my iPad to work as a DJ, and you all may suppose how important was this sync-iTunes-music problem for me and my earnings.
That's my testimony... Best luck for all of you, guys.