Can you save a unit with Zhonya's Hourglass after its Deathknell trigger goes on the chain and still get the Deathknell effect?

Ruling: No, you cannot save a unit with Zhonya's and still get its Deathknell effect. Deathknells only happen if the unit dies.

Sequence:

• The Deathknell trigger is added as pending when the unit would die
• The unit being in the trash is a requirement for the trigger to finalize
• If the unit is saved before the trigger finalizes, it prevents the trigger from finalizing to the chain

Nuances:

• The trigger goes on the chain initially, but the unit must actually die for it to resolve