It looks like a combination of aphids and maybe powdery mildew to me. I think insecticidal soap will actually kill both. Everything kills powdery mildew, even potassium bicarbonate.
I have a similar issue with Pink Pearl grafts. Same grafts on different trees and the trees they are on are completely clear otherwise. No other graft issue. It’s confusing. These are last year’s grafts. I have one remaining graft on Red Delicious that looks ok. I sure hope it stays that way.
I don’t want to be alarmist, but:
Again, I would suspect fire blight, partly because different varieties have different subjectivity to FB and your issue is specific to PP. I didn’t find any information on Pink Pearl and FB, though, so let’s hope I’m off base.
It could be, but it does look different than other cases I’ve seen. No crook, no stem darkening, doesn’t seem to spread in a pattern. Leaves look light colored and dry, then slowly turn brown. I am removing limbs as I see it as I would for fireblight.
I do see that disease resistance is poor overall. Too bad. I was really looking forward to an apple next year.
It’s interesting how pears seem to turn jet black with FB. Apples turn more brown and I think it’s more subtle.
Thanks for your suggestions.