Clarification of creature's subtype for card effects
In Magic each subtype is its own separate thing. So when the Inquisitor says "Human Soldier" it means "this creature is a Human and this creature is a Soldier". Similarly Avacynian Priest couldn't tap the Inquisitor even though it has the Soldier subtype because it is still a Human.

Ghoulraiser would work the same way, the Mauler is a Zombie (regardless of any other subtypes it may have) so it is an option to be returned to your hand.


  205.3b Subtypes of each card type except plane are always single words and are listed after a long dash. Each word after the dash is a separate subtype; such objects may have multiple types. Subtypes of planes are also listed after a long dash, but may be multiple words; all words after the dash are, collectively, a single subtype.
  Example: [...] “Creature — Goblin Wizard” means the card is a creature with the subtypes Goblin and Wizard.