But the part that you highlighted about in season bitches is not likely to occur at a dog show. I do not allow other dogs at shows to lick my dogs nor do I allow my dogs to lick other dogs at a show.
I have not seen any study that shows that an in season bitch is at significantly higher risk than any other dog at a dog show. If you are taking reasonable precautions with your dogs while at a show, I don't see that they are any more likely to contract an infection than the other dogs at the show.
Actually, this past year I bred a bitch who came into season early and specifically asked my repro vet about bringing her to show because it would break the major if she did not show. My repro vet said that it was fine as long as I took reasonable precautions like using a crate and not allowing her to explore the grounds with her nose in everything. She whelped a healthy litter of 4.