It doesn't sound like he understands the first thing about healthy polyamory if the very idea of a family meeting on such an important topic is enough to upset him. As others have said, it's all about communication communication communication! I think I'd be anxious too if I were partnered with someone who didn't have that basic respect for me, for important decisions, or for clear and open, honest communication. I feel for you. Maybe he should read this thread.
Me, 30ish bi female, been doing solo poly for roughly 5 years. Gia, Clay, and Pike, my partners. Davis, ex/friend/"it's complicated." Eric, Gia's husband. Bee, Gia and Eric's toddler.