I had the feeling from what was said by the company that they...

I had the feeling from what was said by the company that they were inferring that someone inside the company had been fraudulently invoicing the company for work/materials/contracts or similar that were not real. It was only somewhat after the event that these costs were recognised as being non-existent. So someone had to have been aware that invoices were received for work that was supposedly done but was not. That had to be someone inside the company, but not necessarily at a very senior level, but you would think it would have to have been senior enough if it had amounted to a significant and substantial value. It also implied that some of the company's trading partners would have to have been crooks too. That could also occur at low or high level. I also picked that it was the auditor that had first smelled a rat and alerted the company at a higher level. All speculation, but we will soon know.

As to the "scientific" paper you mention, the content you describe sounds pretty far fetched and unrealistic. Sounds like something Trump's followers wish was true so choose to believe against all scientific understanding! Phosphorus cannot just disappear. It has to go somewhere and something would have to react with it to remove it from the ecosystem. Nothing like that would seem reasonable to just occur naturally. It would need something to substantially change the industrial agricultural input of P to the ecosystem, or the addition of something like Phoslock to the water systems to make it happen. As to the temperature cooling 5 degrees it would take a pretty big sunshade to bring that about! Or a nuclear exchange between all the worlds superpowers to fill the air with smoke. Nothing less would do the job.