I'm not sure, but I think the fact that Rich is so much the baby of the AIPAC lobby implicates too many people on all sides for many Republicans to want to resurrect this story. Libby was Rich's lawyer at the time, and there are stories about Israeli pressure to get that pardon, so.
Odd coincidences: Comey was the USA (in Virginia, at that point) who tracked Rich down in Switzerland and informed him that he wasn't getting off, would have to make a plea, to which Rich said no deal. Then a few years later, Comey was furious at Clinton for pardoning Rich, but then Comey became USA in NY and led the investigation of the pardon, eventually clearing Clinton and all concerned. And then a few years after that, Comey became DAG and appointed Fitz to investigate the Plame leaks, which ended with Fitz charging and convicting Libby. Small world, eh?