What Is The Possibility Of Contracting Hsv2 From One Oral

Question: What is the possibility of contracting hsv2 from one oral encounter?

the person giving the oral was a man who does not have the virus. the infected person is female have had it for 13yrs hsv2 only one lesion at intial outbreak, no bumps or ulcers at all inside or outside the vagina and only 3 outbreaks over 13yrs and takes daily 500mg valtrex for 13yrs and just for good measure doubles the dosage to 1000mg often. the encounter was not planned and was only for a few mins less than 4. no symptoms at the encounter that was 10-12days ago. the doctor said with having it this long and being on the meds this long and never having bumps or ulcers or visible lesions she believes the risk was very very low, still some risk because the disease is permanent but at this point very low and and i shouldn't be too concerned that the other person has it and that going horse or a cough is not a symptom or oral herpes or that they have it. is this info accurate and what is the risk probability knowing the details in your opinion. do you get it from any and all contact?