Ethan, I don't think Tom was trying to put words in your mouth or anything. Some of the earlier posts make it a bit difficult to know if the photos were current or like the day you got them.
Hans isn't out of business, but he has moved shop (twice)... the first move was to a building that was pretty much falling down. He is getting discus from a new supplier (DiscusX) and no longer sells Stendker, but not much of anyone is going to be selling Stendker here shortly.
I'm 10 months into a Stendker grow out. The good news is your supplier is on the Stendker website, so you should be pretty safe in knowing you actually got the fish you think you did. I'm a bit concerned that there's going to be some shady stuff going on once Stendker kind of slips away... But that isn't likely at all to be an issue here.
I don't know if you've done this already or not, but I think I would make sure to do a course of levamisole and also a course of metro. I cannot tell you which would be best to do first. But if you're already at 93*F, a 12 day course of metro probably isn't a bad idea. I never had all my fish stop eating, but I had a couple of them that would go back and forth for awhile and I wasn't experienced enough with discus to know what was happening. It was tricky because they were mouthing food, but always spitting it out. I am 99% positive that one of the fish I lost was to hexamita (or complications from). Unfortunately it didn't make the 12 day treatment. Got to day 10 and died. The other with the same symptoms (not eating) started eating and has nearly caught up to fish he was at least 1.5" smaller than. The levamisole - I currently have one that wasn't eating, isolated him and found worm eggs in his white poop. I did three 24 hour treatments on day 1, 5, and 13 to the whole tank (after adding him back in). Wiping sides and bottom after each treatment and doing my normal 90% nightly water changes. This fish seems to be in the process of recovering.
What I'm getting at is, I wish I would have been a bit more strict in my adherence to the QT procedures (outlined in Al's QT post)... I let a couple of people kind of talk me out of it on the facebook group and I sent my fish into a spiral and lost one using one of the bacteria starter things (Fritzyme). However, I also feel that that QT procedure could use a refresh to include a course of metro as one of the suggested things. If/when I get more discus to grow out, I will absolutely be doing 93*/metro for 12 days and then after a rest... three rounds of levamisole. The only wrinkle would be if I got them from a smaller breeder that I trusted. I just think there's a bigger chance of having a perfect storm of stress/parasites/disease when you're talking about a bigger operation/importer. The fish I bought were shipped from Germany to Maryland. I have no idea what that process looks like, but it's certainly got to be stressful, which can give hex a foothold. Compare that to someone who is pulling fish from the only tank they've really ever lived in on the morning they're shipping them. That's not to say that there aren't great importers and suppliers, because there absolutely are... and I'm extremely happy with Hans' fish in my case.
There's analogs to the honey bee keeping world that I won't get to far into it here.
The great news is your fish still look good and should have a great chance at bouncing right back once you get the issue figured out and resolved.