I don't get the reported size of the trade exception. It should be bigger.
Pierce, Garnett, Terry, and White combine for just over $34 mil ($34.4 mil if Terry's trade kicker of 7.5% increases his salary for trade purposes).
The players coming back, minus Bogan's undetermined contract, add up to $24.1 mil.
[Edit: I think I see why it might be that small, if the salaries aren't being aggregated together on each side.]