Given the assumption that their balance sheet is liquid enough or they have the cash flow to pay the debts, it's reasonable to say that they have take losses as

Given the assumption that their balance sheet is liquid enough or they have the cash flow to pay the debts, it's reasonable to say that they have take losses as a trading firm to be potentially insolvent. In fact you could turn your argument around to critize the article too, as they are based on the assumption that some of the assets should marked to zero, rather than examining empirically whether those assets could be either collateral or be used to pay the debt.