This is my first home birth and I asked my midwife how she handles GBS positive cases. What she does is sprays the baby from head to toe with a colloidal silver formula immediately after birth. The silver she uses is ASAP brand, and it's specially formulated to kill only the bad bacteria and leave the good flora. That should remove any possible contamination. I'm not familiar with Hibiclens, but I would personally want to avoid antibiotics if possible.
I don't have group b strep. But my midwife reccomends pro biotics daily as a preventative messure. I have been taking florajen 3 pro biotics. There is a lot of information out there about the positive results to women who take pro biotics during pregnancy.