Leaf discoloration/death

[Rusty Trichome]

10) Source of water? (tap, bottled or filtered) What's it's ph before adjusting? Bottled distilled water from Hy-Vee (I can only assume its 7)
11) Method of checking water ph. None
12) Method of adjusting water ph. None

You already know you'll need a method to check ph. Might even need something to adjust ph. But why aren't you using tapwater? (just curious)
It's cheaper to adjust your tapwater, than to keep buying inconsistent bottled water.

13) Specific brand and N-P-K ratio for each bottle. List dosages (quantity per gallon) and current feeding schedule. Schultz 32-10-10, 1/4 tsp per gallon. Fed for the first time 4 days ago.

Is the Schultz in liquid or powder form, or is it a time-release formula? (time release pellets)
How long have the plants been in the MG soil? It takes a month or so before the nutrients in the MG soil deplete enough to start 1/4 or 1/2 doses of your nutrients.
What dilution rate does the Schultz say to use, and how often does it say to use it? (1 tsp per gallon per week, for example) Way high N-P-K ratio. (see below)

13) 14) How often are you watering between feedings, and how much per watering? Lately I have been watering every 2-3 days.

Are you letting to soil dry-out pretty good between waterings? (and feedings)

I got a pH test kit. The distilled water seems to be around 6.4. I put a sample of soil in a coffee filter and poured some water through it and the pH dropped down to around 6.0 =/ so maybe it is a lockout problem. I'll properly test the runoff pH when I get up tomorrow.

You can not properly test runoff ph with one of those ph test kits with color-coded results. Any tinting of the tested liquid will skew the color-coded results. You might not even be in the ballpark for your runoff ph number. Until you can get a ph pen, don't concern yourself with an inaccurate test.
Same goes for ingoing water that has colored nutrients added. The tinting of the water skews results.
MG is pre-buffered and should have plenty of buffers to last aboout 2 months before fading. It's buffered to pretty much neutral ph. (6.5 to 6.8, if memory serves me correctly)

Whatever the problem is, it's getting worse pretty fast. Today the leaf in the first picture is completely shriveled and dead, and the leaves in the second and third picture are much more discolored. I'm afraid the whole plant will be dead within a week if I don't figure out what's wrong. If the runoff pH is low I'll probably end up doing a flush.

My guess is overdose, and possibly ph swings. But more likely it's the nutrients. I'd flush well, and no nutrients till at least the next scheduled feeding day. Your schultz is very strong, and I'd consider lowering your dilution rate to 1/4 of recommended dose.
The ph of bottled water isn't always consistent. My water ph is high, so I use phDown by General Hydroponics. It's a weak phosphoric acid solution that works well. 1/4 tsp lowers my well water ph from 7.9ish to 6.8ish. (a bottle lasts a while)