It certainly can't be cleansed with a derp in charge. He's probably busy rebuilding the derp infrastructure.
I can't think of another federal investigative body, though. Could the military somehow serve that function?
I believe a lot of the CIA functions have been passed off to NSA, based on Q postings.
The ‘other’ fed inv.body would be clean agents moved off-campus to continue their work until the termites are gassed, then they move back home, or another site that can’t be comped. Quite common.