NIXL is supported on a Linux environment only. It is tested on Ubuntu (22.04/24.04) and Fedora. macOS and Windows are not currently supported; use a Linux host or container/VM. For backwards ...
I would start by testing firmware from this repo at v1.27.0 on your board, to rule out hardware/usage issues. Then, with your firmware, try machine.deepsleep(5000) and see if that can wake the device ...