Yes! They sell a NVME hat that I assume is for the Pi5 (these are 4's I had laying around). It also moves the HDMI and USBC to the front.
Its the RS-P11 Expansion board. I can only find it bundled with the normal rack mount kit. I got mine off newegg from a reseller I guess so no expansion boards.
Quality answer. Glad my hunch was backed up by your experience. That's very appreciated.
I hadn't tried anything with Cloudflared and Kubernetes yet so it would be sick to see it just work.