Cold smoked bacon biltong safety
Caveat: I have never made biltong...in fact, I had to look it up.  I do make cured meats like pancetta, dried sausages, and bacon.  By way of example, pancetta is essentially bacon that is not smoked at all.  I use a salt and spice cure, then air dry to reduce the original weight by 30%.  It is then refrigerated.  It can be eaten raw, but in most applications is cooked.

My thinking is that if you are using nitrites/nitrates and salt in your bacon cure, you are greatly reducing risk.  Then, as I understand it, biltong is a dried product.  So, reducing water activity further reduces risk.  In addition, the vinegar creates an acidic environment...also inhospitable to spores and bacteria.  This generally sounds safe to me, but my only question would be about the "hang to dry, approximately 2 days." As I am unfamiliar with the product, I don't know what final texture you are trying to achieve. In general, dry curing shoots for a 30% reduction in weight (the safety reason for this is a reduction of water activity).  If you are going for a jerky-like texture, 2 days doesn't sound like much to me. I see recipes online calling for at least a week of hanging.  Overall, though, I can't see how this would be an environment that micro-organisms would thrive in. I am not a microbiologist or food safety specialist.  Just someone who reads and applies what I've learned, so I would be happy to be corrected if any of this sounds off-base.