I had to take my mom's tomato plants out of the grow tent because it was way to humid for them, if there is any water/moisture at all on the sides, then there is your problem, what is the humidity in there, and where did you measure it, because I thought mine was OK, and then I actually put one of those little humidity and temp with a high/low memory in there on the top of my larger Bulgarian Carrot (put it into a 3gallon pot, has chips on top of the soil, and I stick it right on top) and so I assume the humidity might be slightly higher there than right under the lights, but it gives me a good idea, and the temps are slightly lower since, well now the other plants are beginning to shade it a little.
but anyways when the lights are off, no mater how much I kept the fans on and vented it with the exhaust fan (had it on every other 15min) the humidity was still pretty high, like 80-90% if not higher, but it was just able to keep the moisture off the walls. So now I just have the top front zipper of the grow tent open all the time, it gives a good.. 6" on the top for air to circulate all the time, and the temps don't change too much. and I have a fan on all the time when the lights are on, and another oscillating fan on for 15min once an hour, and a little more when the lights are off + the exhaust fan for 15min every hour when the lights are off, and once for 15min every other hour or so, maybe a little more with the lights on.. but even the Congo Trinidads are doing much better, and they were giving me edema like crazy no mater what I did, they just tend to try out a little faster, I guess they just transpire water through their leaves faster than most.
but that solved my issue, and my plants had pretty bad edema, and the annuums were the ones to first go.. so I think a combo of temps (even if the thermometer doesn't say it's that high, it depends on where it is) and the high humidity in there without being able to circulate "fresh" air, because even when it's really hot and humid outside, and in the tropics.. they still have "new" air to replace and circulate what is around them when they are outside..and the annuums are not as adapted to that.. which is why they went first for me also... and the tomatoes went much earlier on lol, but are doing great now, I just haul them in and out of the mini green house now, and leave them next to windows that face East (which isn't great but oh well, the south facing windows are all filled up with other plants, and my seedlings lol)
oh and last thing, I have noticed that when I let the plants wilt, which I know a lot of people like to do as a factor, but I read and have noticed that letting them really really dry out and then watering them a lot can also aid the edema.. so I have been trying to water them only when they are dry, but right before they wilt, and still have a tiny bit of weight to the pot, but not bone dry, and now i have to pick each pot up before i water them because depending on where they are in the grow room, and their size ect.. will determine how much water they are using ect... it's a pain, but I think I finally got the hang of it, and they are doing awesome now