I don't have a Panda placed, but according to the Wiki:
- Panda Bear - Adds Marble, Steel and Planks for every Pet Food consumed while the Panda remains fed.
So it looks like you are supposed to get bonus Tier 1 goods when you feed another pet with pet food, not when you use EE spells.
I also looked up the original event on Gems and it looks like this is the way it has always been. Here's their explanation of the Panda feeding effect:
Adds Marble, Steel, and Planks each time Pet Food is applied to any pet while the effect is active. The quantity of goods received is based on the stage of the Bear and the total number of completed provinces.
Each Pet Food applied to the Panda Bear activates this effect for 1 hour.