my husband and I are frequent flyer on AA. what do we need to have access to your flagship lounge?

Yes business or first class ticket will allow to the lounge.

It depends on your tier status with AA. From a oneworld tier perspective, one needs to be either sapphire or emerald to access AA and/or oneworld lounges. AA might have different rules for its own tiers. Additionally, North American airlines place restrictions on lounge usage for domestic travel vs international travel. Naturally, if you are traveling in upper class, you will have lounge access regardless of status.

Buying a business or first class ticket also gets you in the lounge.