A Look at Monster Book

Is there a way to know if the Fake Bosses, the ones that were summoned for some event and were weaker than their true forms, drop the cards too?

This has never happened in any version to date, sadly. The only way to obtain Boss cards, aside from hunting the boss, is by getting it from the Maple Leaf Exchange.

that's not to say our Nexon might not do this, but it has not been done before.

Also, Devil's Sunrise did us all a favor and performed a bit of cleanup to the card list. The attributes that the cards add are now marked in blue, and the annoying "n"s where line stops were supposed to be are gone.