Did you receive oral sex in this encounter? My best guess would be that this is HSV1 genitally. While errors do happen with swabs, they are more times than not reliable. For a definitive answer, you could always go for a wester Blot test. Hsv testing is really questionable for hsv 1 at times. It’s really a shame a pcr swab was not done but that is my best advice.
Did you get the culture typed for HSV one or HSV-2? That would really help with the diagnosis. Cultures, well not as sensitive as a PCR swab, are not prone to false positives. Did you receive oral sex during this encounter? Because you’re IgG test came back negative, I would wonder and inquire if this was in fact HSV one. HSV1 when contracted on the Genitals does not shed as frequently and outbreaks don’t happen as often as HSV-2. Also, the IgG test for HSV one is not nearly as accurate as the test for HSV two. It can miss up to 30% of infections. I would check to see if the culture you had done two years ago was tYped.