Hello Dave Unger
Thanks for sharing more details, I have checked with internal team on this.
Your ask would be possible using a flexible scaleset for a nodearray. The flexible scaleset can support multiple nics.
However, the limitation is only one scale set per nodearray (1000 VMs max), and the scale-up/down time is not as good as w/ uniform. But assuming multiple nics on the head node is supported, it should work the same for execute nodes with flex.
Hope this helps.