Meticulous Restorationist

Q: #RiftboundQOTD:

1) When Immortal Phoenix triggers, can I use [Iron Revenant] to pay for its revival?

2) How about when I discard Flame Chompers?

3) If I play a card, what about Meticulous Restorationist?

A: (For now),

1. No
2. No
3. Yes

Mordekaiser explicitly says “only to play units or gear”, which is meant to focus on the game object’s finalization. However cards like Immortal Phoenix and Flame Chompers are triggered abilities with CWI, effectively making it so that the cost is shifted to the triggered ability rather than playing the unit itself (404.1.b.1.). Mordekaiser does not cover costs of triggered abilities.

I think it’s a bit weird that all 3 cards aren’t the same answer, and I’m inclined to believe that Meticulous Restorationist is supposed to be the new standard. I have a feeling that Phoenix & Chompers would receive erratas if they want to be in line with Meticulous.