Maybe Flo is a bit confused as to why she was suddenly 'evicted' and sent somewhere else and that is why she is wary of you. We know it's in her best interest but it must have been bewildering for her.
It's an enormous bonding area. I always feel so cruel bonding in a tiny pen as the poor buns can't get away from each other. A bigger space seems much kinder. They seem very relaxed together. Alex will love your garden - bunny heaven. It's good to 'see' Flo again :love: