Can an IVA stop a controlled good agreement?

Yes

At any time when an application for an interim order under section 253 of the Insolvency Act 1986 for an interim order, is pending, the court may forbid the bailiff from taking control of the debtor’s goods or its subsequent sale, or both, and, stay any enforcement action, execution or other legal process against the goods of the debtor.^[1]

^{[1] Section 254(1)(b) of the Insolvency Act 1986
[2] See Bailiffs and Individual Voluntary Agreements}