Hi,
I am not the real George... ...but I ordered a custom cam from Bullet in 2021, too. I can definitely agree on the lack of info on their cam card!
I also called them and they told me, my cam was ground at 0°. I confirmed it later with a degree wheel (sorry, I don't know the correct english word for it).
8° advance seems very odd, as for example the standard comp cams timing chains only have 3 options -4° -- 0° -- +4°.
At Bullet I had the best luck with one guy named Mike, I think he picked up the phone when you dial the 4 after their automatic message. If I were you I would try to talk to him.
Hope this helps you a little bit and as always: Sorry for my bad english!