but it seems to me that even though he can be upset when being returned to biomom, that doesn't necessarily mean your relationship is harmful to him. After all, by still seeing him occasionally, you are adding continuity to his life, and you are maintaining the bond between you which may come in handy if he should be returned to care.
Here are some things to consider:
Do you feel like she is a competent parent--can you honestly tell him he is safe and loved there?
How does his mom feel about the situation? If it is upsetting to her, and therefore causing friciton between the two of you or between her and her son, then maybe a break is needed to let him reestablish his connection to her. It doesn't have to be permanent.
Can she learn from watching you? I don't know why he came into care, but it might also be the case that observing your parenting style could help the mom if parenting skills are an issue for her. Maybe if you visited him at home with mom, or went to a park with his family or whatever, he wouldn't see the two of you as separate options?
again, I am a mom, not an expert. These are just things I would think about if it was me. Good luck with this--I think it speaks well for you that she wanted you to go on being involved. GIve yourself a pat on the back
