Nutrients

It looks super frosty, and that frostiness is related to phosphorus utilization...so the plant is sucking it (and other necessary mobile elements) from the leaves for the flowers coz the phosphorus is pretty much central to internal energy, and flower/oil/seed production.

Uh, if I were you, I'd (also) lay off nitrogen stuff. Then I'd use some calcium (not much magnesium), phosphorus, citric acid and some microelements. The trichome coverage and discolouring to me suggests mainly that the plant doesn't have enough phosphorus uptake. And the shit I mention there, is mostly to alleviate some of that. As your flowers there are practically using all the phosphorus in the plant now.

I'd look at the N P K ratios before feeding and be careful. It's not normally recommended to mix brands. In early/mid bloom you want an N P K of 1 3 2. in late you want 0 3 3. Just be careful with the N. (Cal mag has N in also)