Personally, I think surviving an attack on their HQ by virtually every supervillain in the world counts as "victory."

However, about the card:

Ongoing: At the start of your recruit step, if you control exactly six characters with the printed Secret Six affiliation, you win the game.

How are we to read the application of the word "exactly"? If I control six characters with the printed Secret Six affiliation and one GCPD Officer, have I met the requirements or not?

"Exactly" either refers to the number of characters you control with the printed affiliation, or the number of characters you control.

But which?

--carbonbased

It would refer to the number of characters with the Secret Six affiliation. So, 6 S6 and 1 GCPD will still qualify.

Otherwise, it would be 'if you control exactly six characters, each with the printed Secret Six affiliation.'