Second hand clothing

In need of advice as I'm so worried now! I've basically tons and tons of brand new clothes but was gifted new and nearly new aswell. A family member trusted a friend of theirs for baby clothes and there was loads new with tags, but I discovered one vest with black stains, Initially it looked like a hair dye spill to me then found another and an outfit with the slightest grey dots. I put them in boiling water, washing up liquid, lemon juice, talc and baby safe detergent then a hot wash. Since they smelled fresh washed I thought this was harmless but now I'm noticing black mold or mildew looks very similar. Do I throw out the clothes that had the stains, do I throw out everything I remember came from this friend? Do I let out the ones she had tags on unused too? My own good friend gave me baby clothes too in great condition with no stains so I actually am unsure what came from who. Is it looking like I should toss everything unless it definitely came from the friend thats clothes were all ok?