Ok, I took a look, and I was glad you are using 8.5, as I still am as well

Anyhoo, I also noticed that you didn't truly have a "Collision Event" setup, I believe you may have simply selected the animated plane + particleShape and chose "Make Collide" in the particle menu correct?

Sadly, this is not a "true" collision event.
Well, it is, but just not the type of collision you needed

Check my attached edited version of your file.

All I did was select the particleShape + the animated plane and in the same particle menu chose "Collision Event Editor" and created a collision event with the following settings:
-All Collisions (change this accordingly for further events)

EVENT TYPE:
-Spread: 0
-Target Particle: particleShape1 (your original particleShape)
- Inherit Velocity: 0

EVENT ACTIONS:
-Original Particle Dies: Checked ON.

Then wen I rewound the scene and played it back the animated plane hits a few particles in the original particle sphere you created, but those particles die, and in thier place, a new particle is born that react to your gravity and fall to your floor.

BUT, they are not affected (moved around) by the animated plane.

Is this closer to what you were looking for maybe?