From my physio therapist "If you have an active inflammation response in your joint, it is always best to rest it up and practice P.I.E.R. Pressure- controls the inflammation, use of a tensor bandage to contain the swelling is appropriate, Ice- 15 minutes per hour, Elevate-lying on couch with knee about 10 inches above the heart, and most importantly Rest- as in no participating in potentially aggravating conditions. I would have to qualify the knee brace you have to see if it will restrict the motion of the ligament that we would suspect. If it is just a warm neoprene sleeve like brace, it won't do much for the stability of the knee.
I never like adivising people to sit out of their event or training, but I think your knee may have already made that decision for you. So, it may be best to sit this one out Amanda."
I will defeat the next challenge but must sit this one out!