We have a rehire who took a distribution while terminated. At that time the nonvested monies were forfeited. Our plan document allows for the restoration of forfeitures, but only if the vested monies are repaid.

My question is: does the repayment need to be from a pre-tax source, such as an IRA or other qualified plan?

Thanks in advance!

Not only is the answer to your Q "No," but I don't think there is any published authority that would permit a qualified plan to limit buy-back rights to pre-tax amounts only.