This looks good. The [numa] sections in qemu.conf look different than with LXD 5.2, but the new one generated from the fix-wrong-numa-template branch is correct. Here is the generated qemu.conf from that branch:
With LXD 5.2 the node-ids went up to 3, but that’s a machine with 2 physical CPUs, so node-id should be only 0 and 1. The memdev settings look better too, in LXD 5.2 it went up to mem3, but the fix-wrong-numa-template branch generates until mem1 only, which is correct.
For context, this machine has 2 physical Xeon E5-2670 v3 CPUs, each CPU has 12 cores and each core has 2 threads.