We already have a pretty good understanding of how it happened, as 2/3 of the cases involved donors with a stem cell mutation which lacks receptors capable of taking in retroviruses. Several more patients are in remission, which means it is actively undergoing human trials, but it takes years to be officially declared cured.
And one more bit of good news is that there are small communities in South America which the locals have tested positive for rabies antibodies after being bitten by a bat despite never receiving a vaccine. People everywhere are awesome and developing natural resistances to what was once a death sentence, as well as curing the most incurable ailments are proof of that. I hope y’all enjoy the good news from the medical community :D