Counterspell + Shirvallah Cost Negation? (Dalaran Heist, Not Sure If Bug or Game Mechanic)

So, I was playing the new Dalaran Heist as Paladin, had an entire hand full of Shirvallah’s do to some sillyness. Played against a boss that spams Secrets. They had Counterspell several times.

I noticed that when a spell got countered, Shirvallah’s cost didn’t get reduced by the spell cost. I looked up Counterspell, and its description says “The spell card will still be consumed and its mana cost expended.”

Shouldn’t Shirvallah’s cost have still been reduced then, since I “spent the mana on a spell”?

(Sorry if this has been asked before or isn’t a bug, I’m not really a Paladin player.)

Might not have been clear. I lost the mana, as usual. But Shirvallah’s cost didn’t reduce for the mana that was spent. That’s what I’m asking about.