There's a difference.

Add that to the fact that Moiraine is the only person besides Rand so far to actively HUNT a Forsaken (Belal) and back when they were actually scary, at that. She also attacked Aginor (or was it Balthamel?) back in EotW, despite knowing the futility of such an action.

If that wasn't enough, she bodily threw herself at the most powerful female channeler in the world, AFTER giving her an angreal to play with. Even if she knew there was a chance of survival, how many people would actually play those odds?

I think Verin was of similar bravery, but not necessarily in the same way. Siuan too has never gone toe-to-toe with a Forsaken.