Potential Athenes bug on Invasion mode?

I played as Soraka in multiple Invasion mode and I'm a little confused as to how it's interacting with the PVE monsters. I damage enemy 'champs' like Cho'gath and Velkz, but Athene's stacks only seem to go up a random times. Things get a little hectic later in the mode so it's hard to see if my healing is being increased regardless whether the stacks are visible on the Athenes slot or not. Are only some of the enemies considered 'champions', or none at all?
Report as:
Offensive Spam Harassment Incorrect Board