Odyssey Blue X86J4125 and IOMMU

I’m trying to configure the Odyssey Blue X86J4125 to use IOMMU.
The latest firmware is installed dated 05/20/2022.
In the CMOS, CMS Support is enabled. It shows the CSM16 Module Version 07.82.
Network is the default UEFI

Under debian, when I run dmesg and search for IOMMU, I expect to see that it is enabled, but I get something else.

dmesg | grep IOMMU
[ 0.112007] DMAR-IR: IOAPIC id 1 under DRHD base 0xfed65000 IOMMU 1

In Proxmox-Hardware, when I try to add a PCI device I get
No IOMMU detected, please activate it.See Documentation for further information.

There are also configuration settings for a Network Stack Configuration, and the default is Disabled, are the defaults OK?

This board is the X86J4125 V1, is there a difference in IOMMU with V2?

In the big picture, I want to run Proxmox and either OpenWRT or pfSense but without IOMMU support this will not work.