That scenario looks fishy to me, even when you buying second hand car you do bit of exploration and for buying something with price tag of £11,000,000,000 well you dig a bit deeper, and due diligence is not just going to your financial statements and what is usually accessibly in UK publicly. During that process you dig trough everything, bank statements, expenses, salaries, earnings, revenue streams ... everything.

Personally, I think it is impossible HP has not seen something like that, or they have sent complete idiots to do due diligence.