I thought it was the EPA, not the FDA, that regulated pesticides in the US. I have no recollection of reports of either the FDA malfeasance you claim nor of any reports of widespread re-import of domestic bee colonies. In fact, I had thought that importation of such colonies was pretty tightly regulated due to pathogen and parasite concerns. In other words: citation needed.
Without stipulating that this actually happened --- that bee farmers today are relying entirely on Australian imports --- you're still begging the question. Why? What difference does it make?
Personally, I think any mass death event of an important species is extremely worrisome, irrespective of their source, and necessitates root-cause analysis and careful examination of the current equilibrium.
FDA panel found the link, they recommended stopping the chemical.
The head of FDA pocketed the research/recommendation in his desk until "further".
It was half a billion dollar industry of which that guy got a piece of the money through some channel.
Net result:
USA had to import bees from Australia.
EU banned the set of chemicals
My grandfather, after 50 years of bee keeping lost half of the swarms, until we figured out what's happening and what's killing them.
Lobbying shoduld be made illegal.