Method for gathering feedback during prototype demo

The current situation doesn't allow me to do one-on-one user testing, so the account team and I have agreed to demo the prototype to a small group of 2-3 users at once. I couldn't find any resources for getting user feedback while conducting a demo (checked DesignKit, HyberIsland, and Gamestorming).

The current plan is to effectively "group audit" a few of the key users tasks with the prototype, while asking both open-ended and targeted questions. The session audio will be recorded and someone will hopefully take notes as backup.

Has anyone come across an established approached for demo feedback?