Well, we went to Epcot Saturday and used our new idea for connecting mine and MJ's wheelchairs together, and it worked!!!!

I have a collapsible companion chair and hers is a stroller type pediatric so when they are hooked together they are not much wider than a double stroller. We got those clamps that are used to hook umbrella strollers together, 3 clamps to a box, the box is 10 bucks. So we clamped those on and then used a clamp around that for extra support and stability. It is removable if needed, but we didn't need to that often. In narrow ride queues we transferred to a rental chair with her in my lap if our chairs were too wide, but we only had to do that a couple times. Overall it worked really well!

Hopefully this might help other families who have two wheelcahirs in a group!