I don't mean to sound picky but why shouldn't you need to know what brand it is?? I personally would want to know what i'm using on someone's nails. I can't say i've heard of a yellow gel, but i've only seen a few.
What would you do if a client asks you what make it is? I don't think it looks good if you don't know. I know loads of people that have got to know various brands of acrylic or Gel so they tend to go for certain makes, i would really try to find out if i were you, otherwise you could be using something that could be a cheap make that gets results but doesn't last or wear well, or even goes yellow.
Hope you find out, let us know.:|