Are they doing well? Well, they grew from when I planted them! They exist! Some do not exist anymore. Which is fine. If they all fruit I'm dead from canning. I'm happy with them!
You may still be able to transplant them. Tomatoes grow like weeds. The way you have it set up they will grow but each plant will have fewer fruits. I plant 2 per 4x2 bed and they will fill the entire thing and then some. Add some herbs or strawberries for a great companion plant.