1. Is it possible that the IgG is showing a false positive for HSV1 given the value? I feel like I read somewhere that the result is within a possible false positive range. I’m also concerned about the result given that (a) I have never had any cold sores on my mouth, (b) I have never had (noticeable) symptoms on my genitals and (c) the swab test was negative.
Yes, it is possible that this is a false positive. It is also possible that this low index value is due to new infection (I think that is far less likely). I would suggest that you repeat the IgG only 6 weeks out from the encounter and see what you get. If it remains well below three, you might consider a western blot for confirmation or denial of your HSV 1 infection status.
2. If the IgG is a true positive result, is it possible that the test is picking up HSV1 in the genital area? Would the positive IgG result pick up a recent genital infection (HSV1 or HSV2)?
Yes, it is possible
3. What do you think about the negative PCR test result? Is it possible that I have an infection that the swab missed even though I’m now at day 11 after possible transmission?
That is also possible yes. That’s why I am suggesting that you repeat the IgG test and if you get any more skin changes or lesions, get them swab tested again, hopefully using PCR