Sorry, this isn't correct. What has happened is that due to the revaluation of the underlying assets, too much performance fees have been accrued so they now need to be reduced. What this means in practice is that assuming the assets are sold at today's valuation, BLA would receive $7m less in cash than it was expecting to under the previous valuation.
Granted, BLA does not have to pay out $7m in cash today, but it does mean that in the longer term they are expecting to receive $7m less in performance fees than they had originally anticipated.
Of course, if the value of the underlying assets subsequently increase, further performance fees can be (re)accrued but it isn't right to say that this is equivalent to a non-cash writeoff like a diminution of goodwill.