I think the "brain" is the led bleaching the bud from too much light, very similar to what happens when they get too close to my hps.
I can only use a jewelers loop to see trichs, i cant focus using the little microscopes they sell, luckily i tried it in store before buying.
I would do a straight water flush for a full 2 weeks, no guano in the tea at least, but i cut out everything thing personally, just water for 2 weeks.
My guesses on harvest is about 2 weeks for the one with more red hairs, but more like 3 or so for the one with the "brain". Just my thoughts, one of the toughest things to judge is when to start flushing.