Sorry, I don't see any connection between failing to make a cash contribution to a defined benefit plan (which, whether cash balance or not, has no impact on the accrual of benefits) and Section 401(a)(4). There may be a qualification requirement associated with meeting the minimum funding requirements or a failure to carry out the plan provisions (assuming that the plan demands that minimum funding be met), so I am not saying that failing to make the minimum contribution to the cash balance cannot have an impact on qualification, but I am saying that if it did it would not be a matter of failing to meet the non-discrimination rules.