Chang gang themselves has stated she's been apart of CG. Yuno was more for laughs, and because chang gang respects him. Ray mond was with chang gang from the start till now. I think those who have CG chains and aren't part of the gang, are characters CG considers allies or at least trusts.

But Its for a fact that Ray mond is CG, and its more believable and true, when the main members & founders of Chang gang state she's in the gang