I think you're confusing retail with 3.3.5a

Revive Pet - Channeled, mana cost, requires corpse (in world or despawned)
Call Pet - Instant, no mana, requires a living pet (dismissed or despawned)

If the pet is not dead, CheckCast should error immediately saying "Your pet is not dead" so the Hunter doesn't channel and can use Call Pet. Likewise, if the pet is stabled, Call Pet should say "You don't have a pet" (remember, call stabled pet is not relevant to 3.3.5a).