I’ve never wanted ppt to automatically advance slides. I want to advance them manually, as i speak. I’ve run zoom and also shared the slides, and didn’t have any trouble. (Or maybe it was teams… Hmm. I have used both extensively, but teams more with slides.) You just have to have ppt have focus when you switch slides.
That being said, this sounds like a large formal meeting, and it’s always better in that situation to have someone other than the speaker run the zoom session. People will join late. Random people whose identity you want to verify will join. People will want to ask questions and the speaker may not notice. It’s just better to have a designated person to handle all that stuff. Even at live meetings, there’s often a moderator as well as a speaker.
Both the moderator and the speaker will have to be running zoom, though. The moderator to control the meeting, and the speaker to share the slides, so remote viewers can see them. But if the moderator is interacting with zoom, the speaker should be able to set stuff up and background the zoom controls and ignore them.