For some reason, blueprint isn't affecting anything in the world

The title may be a bit confusing, so let me elaborate:

I’m trying to implement powerups into a blueprint/c++ game. C++ manages the detecting of the player overlap and calling of the On Activated event, but for some reason, blueprint is unable to do anything to the game, even though I’ve confirmed the event is being called.

Here is my blueprint setup:

For some reason, the Print String runs, but none of the other nodes do anything. I can put the Print String anywhere in the node setup, and it still runs. It also seems if I try to run a blueprint node from anywhere in the actor (ex: spacebar), it also doesn’t work. Does anyone have an idea why this might be happening?

Here are the c++ classes powering the powerup:
[SPowerupActor.h][2] [SPowerupActor.cpp][3]

[Here is the troubled Git commit][4], if you need to see any more files.

Any help would be appreciated.