I'm sorry that your daughter hasn't yet responded to ATG.
Low platelets is not an established side effects of Danazol.
There have been individual reports of decreased platelets by people taking Danazol but it's never been found that Danazol was the cause. There have also been individual reports of increased platelets.
I think that means that the answer to your question is that it's unlikely but possible.
You didn't say why your daughter is taking Danazol, i.e., for angioedema or another condition. Depending on the reason, her doctors could consider other medicine that treats the same condition. Each medicine has its own benefits, risks, and possible side effects.