According to CH wiki this card makes "All enemies discard all blocks". However, in the video right here: min 9:30 you can see "All enemies discard all attacks". I'm surprised. Did it was updated? PD: Notice that Wail is not displayed as an 'unblockable' attack. I think this is an important point.
I don't understand what you mean. None of the Castle Mitternacht monster have been added to the wiki Bestiary. Wail discards all Attacks: "All enemies discard all Attacks." If you're seeing the discard all blocks version, you have the old one cached on your browser. Wail is not unblockable. In the video above, CT5's warrior had a Laser Block, but couldn't block the Wail, because the shade was behind the warrior.
A last favor. Wiki was updated and its big picture too, but not the small one. I may need it for my posts or Aloyzo's contests. Pleased i'll be Pawn.
Because the one operating the update semi-automatic scripts has been gone for quite some time and nobody hasn't volunteered to add those monsters manually.