This panel can talk about what they're doing to drive the initiative and ideally there are no DEI/People people on stage at all aside from maybe a moderator. If there is no diversity on that stage ... ask them what they're doing about it and if it's a goal for them to drive inclusion at all levels.
Also, big monthly meetings are an anti-pattern. Once high level people are participating, you will hopefully see the frequency go down and the quality go up.