After a full day with support on chat and phone, restoring the iPad in every way possible, backup, no backup, new iPad, etc. I went to an Apple Store restored from their local copies the latest iOS, they said there's nothing more they could do. In desperation I ended up buying a new iPad :( and it slowly worked out and pushed the Notes tothe new one. Till that point, the last guy in Support said that they were going to take this bug to the engineers cause there's nothing more to be done.
It seems that somehow the error damages the communication between Apple Notes, iCloud and the hardware id with the database in iCloud, that's the only logical theory an Apple Genius said it could be happening, and there's no way to be fixed, at least until yesterday, October 24th.