no, there is not a test that can tell exactly who she got it from.
If one of her partners tests negative for hsv2, then she knows she didn't get it from that partner. If both of her partners test + for hsv2, no way to know which one infected her.
make sure she reads the free herpes handbook by Terri Warren or picks up her book "the good news about the bad news" on amazon. Both are terrific resources for her to better understand her infection so she can deal with it and keep the risk of transmission to future partners minimal.
grace
Hi and welcome. Tell us about the test report as the numbers could infer old or recent infection.