when i zoom in, the bit in lower left just looks like a clump of trichomes...
but, if you have a proper scope, get in there and if it's moving, then it is clearly infested. Some of it is too blurry to be certain, but i see stalks and bulbs in some of those clusters.
got a 30-60x scope? can make sure no creepy-crawlies there, as some are quite small.
Also, should see some sort of wrinkle/etc on other side if something is sucking on leaves.
Also, with a scope you can ensure it's not a fungus/mildew/mold. I do not think i see any reason to believe it is, but need a scope to see better.