Didn’t get to ask any questions in last interview, how to ask if I can chat with the team?

I’ve had three interviews so far, the last being a technical with what would be the direct team. It was INTENSE and I didn’t get a chance to get a feel for the team or ask ANY questions. Like they left no time at all. I didn’t bother following up as I didn’t think it went that well, but now they have asked me for a fourth and final interview with another team. I’ve agreed, but I also want to ask if there is potential for me to speak with the direct team and ask them a few questions. Basically, I’m worried about culture and so I’d like to talk to someone besides the hiring manager or HR, but I don’t know how to phrase this when those are the only people I’m emailing. Any thoughts? Or thoughts on if not allowing questions is a giant red flag? Or if I should just wait til I have an offer?