Mik1,
You are right that 65B is a small portion of the total Assets but it won't be the end of the story. As long as there is asset remaining in the Balance Sheet, the distribution will continue or it will depend on whatever the next decision they may have. That is if they will decide to go back in business or to continue the distributions. Some of the creditors and Debtors claims maybe satisfied in full and some will be paid only in part of their claims but Lehman will continue to to turn the remaining assets available for the next distributions.
Selling of assets is a different story than the distributions. The values of the Illiquid assets in the Balance sheet is of course cannot be exactly the same with the selling prices but for sure will be very close as they will keep it updated to it's market values. In fact, There is only about 27B of cash available in the 65B distributions and the rest are illiquid. Those illiquid assets can only be distributed by crediting the Debtors and other Affiliates on their financial obligations to Lehman. Realize that Lehman also have claims against the Debtors and Affiliates and the distributions will just balance out or reduce their obligations. The illiquid assets therefore will remain to Lehman's.
I hope I answered your question completely.