I hope she pulls through this.
I don't want to be pessimistic, but myxi can be very deceptive and the bunnies are often lively and eat well for a couple or three weeks and then suddenly go downhill. This is what happened with my baby. She was "fine" for three weeks and then got worse within hours and died.
The course of the illness also depends on the strain that Colby has got (and yes, with swollen genitalia and puffy eyes, I am 99% sure it is myxi), some strains of myxi are less deadly than others.
I do hope you are lucky as some bunnies are (you can see some success stories on the link I gave you above), but I think you also have to be prepared for the worst.
It is a good idea to keep contact with your other rabbits to the minimum. That's what I did. I also changed my clothes every time I entered their room to avoid cross contamination.
Keep us updated on the little one.
Vera