Dismantled discretionary trust and effect on NRB

Married couple, the husband died intestate in 2006.Due to the NRB rules at the time not allowing transfer the surviving spouse was advised to complete a DoV and set up a Discretionary Trust which put a charge on the property of 50% of the NRB at the time. (£137,500). The trust was subsequently dismantled in 2017 and the property was sold without a charge in 2018. I assume that the original DoV will still apply because of the 2 year rule and the 50% NRB will still be deemed to have been used and that the NRB for the second spouse (who has now passed) will be £325,000+£162,500=£487,500? Could someone kindly confirm for me please?