Instagram is pushing reels and post captions thus rewarding profiles that can retain eyes longer.
Unless you are ready to start posting reels and expand into video, you should pump the brakes on high expectations from Instagram.
That said, I flood the market myself, since my goal is to grow. Reddit, Instagram, Tiktok, Facebook, Flickr, Youtube.
This sounds like clusterfuck waiting to happen. Headshots at a party? Who's going to be suited for what I assume to be a professional headshot. They are setting you up for failure by not just ponying up the money for a professional photographer. Not saying you couldn't learn how to do the job, but on so short notice, with your lack of experience and equipment, it'll end up with subpar results.