The QF balance sheet is the problem. They cannot afford to order new jets, or lease them as things stand. The orders they have currently are almost too much for them to finance given the current financial state of affairs. They may have cash in the bank, but look at the committed liabilities of the group and you get the idea. More than the cash in the bank.
There have been many opportunities of late to secure opportunities, but the rapid growth of the group (read JQ) has eaten into the parents buying power.
Why would they be keeping 767's, and deferring 380's and 787's. The future for international is codeshare now.