If the pellicle has the type of bacteria or mold on it that would prevent you from eating it, you should also generally not eat the rest of the meat. Not all mold can be told apart by appearance, so please do not take this comment as gospel on what is a "safe" mold, but the general consensus is that white mold is usually OK. In this case, I would not reuse the parts that were moldy, however.

I have a dedicated dry aging setup that I truss my subprimals up in, and then it recirculates air, including through a UVC light. I've never had any mold form, even on 120+ day dry ages. I haven't gone much higher than 120 days, though - I enjoy 240 day dry ages, but not in large quantities, and I also lack the patience, so you might see more going to that length. But in the 60 to 120 day range, however, I have never had mold form in any quantities large enough for me to notice.