I think those children are blessed to be safe with people who are responsible and love them.
You did the right thing to report the false tests, sadly they are more common than most people think. The only accurate test is done while watching the person pass urine, or through blood or hair tests.
I'm glad you found us, we have a special place in our hearts for grandmas who are raising the children, we even have one wonderful great grandma here and she's doing a wonderful job raising a lovely little girl.
Hugs