Atheros Bluetooth on Mac Mini G4 1.42

Hello -- I'm trying to get bluetooth to work on my newly acquired old Mac
Mini G4. Nice little device running NetBSD 10.

I'm using the macppc GENERIC kernel, which has:
aubtfwl* at uhub? port ?

Following man aubtfwl.4, I downloaded the firmware and copied to
/stand/macppc/10.0/modules/ubt/.

Upon rebooting I don't see either aubtfwl0 or ubt0 in dmesg.

Am I missing a step?

More of a mystery: At some point, before I copied firmware, I did notice I
somehow triggered this in dmesg:
[  2936.203280] aubtfwl0 at uhub4 port 4
[  2936.403380] aubtfwl0: autoconfiguration error: 'ath3k-1.fw' open fail 2
[  2981.276292] aubtfwl0: detached
[  2981.276292] aubtfwl0: at uhub4 port 4 (addr 5) disconnected

I have no idea how that happened, but it at least made me look at aubtfwl.4.

Thanks - Joel