When was the last major bust?
In my opinion, the last "major" case was LIUNA's takeover of Local 210 back in 1996. As said above, a decade later it was declared free of mob influence. There have been some relatively minor mob cases here and there since then but nothing that suggests a very active family.
I have no knowledge of the Buffalo family, but I have seen this question posed in other threads previously....namely, that if there hasn't been a major bust/trial that there is no organized crime....this is just simply not the case...most cities have little to no FBI presence that is the least bit dedicated to LCN activity...whatever presence they have is spent on counter-terrorism and/or white collar crimes. I am certainly not sure, but my guess is that a city the size of Buffalo probably only has 2 or 3 agents total...so how much time could they possibly give to watching an anemic and limping LCN....and this is the case in most cities outside of NYC.
Cases, or the lack thereof, are actually the best sign of mob activity - at least over the long term. Perhaps one can use your argument over a short period of time. Say, 5 or even 10 years. But as more time goes by, and the lack of mob cases in an area continues, that's a clear sign. It's not just a coincidence there are a lot of mob cases in New York, less so in Philadelphia, and none in Denver. Take Milwaukee for example. It's been 30 years since the last mob case there. Does anyone really believe there has been a formally structured, viable family operating there during that time?