...I can't help but wonder if the orgs that were customers of Brundage will have any certifications they gained by using his recycling business revoked and if they will be fined for not meeting attainment goals retroactively.
I would certainly hope not. I am responsible for small scale hazardous waste collection at my workplace - mostly metals like lead and cadmium as well as toxic organic compounds - and I can say that the process of disposal is heavily documented with a clear paper trail. When the waste is picked up and removed from the premises by the waste contractor, I have to certify that each container holds what the label says it does, then once the waste has been treated I get mailed a manifest certifying that it has been safely transported to the processing facility and properly disposed of. So long as I've correctly identified the waste (say, I haven't tried to pass off a mercury compound as some other metal) once I receive the paperwork stating that the contractor has done their part, I'm legally off the hook as to what happens to the waste, since without actually observing the processes at their facility (and being able to understand what I'm seeing) I have no choice but to take it on good faith that the waste was treated legally.