Germination can be a little tricky. You basically have soil, light, temperature and moisture as cultural conditions to deal with, you only mention misting and a reference to led lights I don't quite understand. Keep in mind not all seeds require the same cultural conditions to germinate. Some need light, somewhat dark, some like mild, some like cooler.
Your wilting almost sounds like leggy i.e. not enough light or not enough light and then you hit them with light that was too strong or hot. Generally you want plenty of hours of balanced light i.e. not hot and not so bright you need sunglasses and not dim. A fairly even temperature for a large portion of the day. Lots of flowers seeds (what I mostly grow) like about 654-75 degrees or so. Watering, I don't know how much moisture you loosing, but try to keep the soil moist, but not wet, sounds like you’re doing that. Careful not to beat up the seedlings when applying the moisture. Did you up the moisture once they germinated, maybe too much water? For soil, I tried what you’re using but I found it to be hydrophobic at times and expensive. A high quality potting mix with the chunks and lumps taken out works very well.
Also what did you start them in? How long had they been growing? How long did it take them to germinate, how long after germination till they went south? A picture or further describe would help.
Here is one of my germination efforts, I have come up with a better lableing system

. Even with my semi-automated set up (water, supplemental light, trays, fan or heat when needed) I don't always get the germination I hoped for. A little too much water, a hot spot, a dry spot can have a big impact.
Keep after it, do some more, try different things.
From here