Possible issue with the H6005 bulb
This is just based on code inspection, but AFAICT the H6005 bulb should be listed in the bleColourD list at about line 487 of lib/utils/constants.js.

I have a Govee H6005 bulb and am adding support for it in my own app. When I send a color command to my bulb based off of your code (sending a 0x33 05 02 RR GG BB ... ), the command doesn't work at all. When I used a 0D instead of the 02, it works great.

This is based on the code at https://github.com/jonahclarsen/bluetooth_lights_controller/blob/main/bluetooth_lights_controller/bluetooth_led.py where they learned the same thing.

BTW, I'm loving all the work you and everyone has been putting into the Home Bridge project.