Apply Point Damage - Damage Causer within Widget

Hello everyone!
Currently running in some issues using my Render Target Painting tool.
One of the main events i have to run for getting this done is: Apply Point Damage. Apply Point Damage wants to know a ‘Damage Causer’.
If I wouldn’t have placed this in a Widget, I would have less problems, 'cause then I just could easily place a reference to ‘self’ and everything should work fine.
But I couldn’t make up a solution for placing a reference to self in a widget.

Is this even possible?

Thank you very much in advance.