but if the bun is left there it will die so it would be better off living in a shed. Hope your husband can catch the bun and I hope the other 2 are ok aswell. x
This is a good point, domestic buns dont dig burrows so they wont have any real shelter or protection from predators, plus myxi season is coming up and I assume there are wild buns around. If by some miracle they survived until Autumn they would then die from being soaked constantly and the cold... Don't forget these rabbits aren't wild. And if you do manage to catch the others too they can be reunited.
6x8=48 the rwaf minimum is 44sqft, so that space should be fine, they have probably come from much much smaller. Remember you always have the option of rehoming if you don't feel up to keeping them.