If both facts are accurate, it means that the government has committed itself to paying $3B--minus expenses--worth of rebates, but has only gotten around to paying 3% of that, so it still owes the remaining 97% to dealers.
While I am reluctant to credit this administration with anything, the statement that the program is running out of money while it still has cash in the bank to pay its backlog of bills (in other words, the use of accrual-based accounting) is a departure from the normal Democrat use of cash-based accounting for such things. I don't doubt that the decision to use accrual-based accounting in this scenario is driven by politics more than honesty, but at least the program isn't giving $10B of promises.