I agree with Bob here. I’ve seen some of the yellow as well on stems. I just wiped it off or cut it out. That last pic, I’d wipe the leaf off because sometimes sand, dirt, and such can be on them. I would be more concerned about white mold that is in LARGE patches. This doesn’t appear to be the case looking over the pics here. I would suggest that if you end up finding more, set em aside and let Don know at WLT. Don has always taken care of any questions and is willing to work with, and make things right for his customers.