Leaf symptoms look viral in nature.

[Paradiced]

sorry for the super long post. Bear w me please. I'm really anxious to get any input from the farmers out there. I haven't even had time to think about anything I just saw it and I came right here so this is my first very first course of action.
I just noticed one strain in particular Mandarin Sunset there are clusters of leaves that look like they've been to a torture chamber. Overall the plants look wonderful. All growth parameters spot on everything moving along very consistently. I caught these crinkling leaves out of the corner of my eye and on closer inspection it seems like they are confined to the inner part of the plant ATM. I would not have suspected anything because all the growth looks good and normal, no red flags, so this has caught me by surprise! This room was flipped into flower yesterday. The media is coco 70/30. Lighting is 1000 watt hps DE. Nutes are Flora duo running them about 800 PPM. CaMg and Power Si in addition.
I'll post pictures of the leaves and then the cluster of the affected leaves as they sit in the plant. Whatever this is it happened over a very short amount of time, within the last 3 days if I had to guess.
I've had an indoor virus issue before many years ago. The one thing I learned from it is it was the worst f****** experience of my growing career. Hands down by far blows away any mishap I've ever had regarding farming cannabis, flowers or vegetables!
Pictures coming right now

 

[Paradiced]

I know the pics of the plants it's hard to tell what's going on. Try zooming in to notice the clusters of affected leaves. I'm pretty certain this is not the plant naturally shedding leaves as it does throughout its growth cycle. The clusters are too concentrated. Thank you one and all Farmers for any input or any direction you could point me into.

 

[Paradiced]

The first picture of the leaves showing the undersides notice the subtle dark splotches.

 

[Paradiced]

Make that second picture that shows the underside.

 

[Paradiced]

Just so the farmers know, I keep my flower rooms very clean and stay on top of all preventative maintenance.

 

[Paradiced]

I pulled out 6 mandarin sunset. The fan leaves continuing to shrivel and die. Like someone took a flame thrower from the inside out. Once it reached the actively growing tips is when I yanked and buried them. No plants in the vicinity are showing the same symptoms as of yet.
I just figured I'd follow up cuz I got a little panicky LOL. So far so good. I started spraying zero-tol when these symptoms began and am currently spraying 2x/wk.