So, I've read through posts, I never add nutes when trans planting. What I do is this, I fill the new pot with soil, add some water, this is done to be sure all the soil is moist, then i make a small hole, actually use solo cups so i push cup in to the level it will 'sit', add 1/4 teaspoon of mycos, set plant in, top off with soil, then litely water the added soil. Thats it. I keep light 3 to 4 feet away from a single 600 until plants show signs of growing, by then they have 'hardened off' and now can be set closer to the light. cooler temps are at floor level and B4 lights come on a certain amount of wilting would be normal. I think too much went on in the initial trans plant. Your soil already had some ferts in it. If you are 100% sure that all the soil was wet (especially under the cube), then overwatering is likely. What changed from the photo that shows a healthy plant, to the last photo where its all droopy?