Armbian requires the latest UEFI firmware for this board available here: https://forum.radxa.com/t/radxa-dragon-q6a-firmware-snapshot/
For flashing the (extracted) armbian image to UFS storage you can use the same edl-ng
tool from flashing the firmware with this command:
./edl-ng --loader prog_firehose_ddr.elf --memory UFS write-sector 0 *.img