Bex, is right. Try another dealer. Swammerdami are awesome and I believe they are THE biggest.
What I would do is, just let the Swammerdami come home. Forget what happened. Take a fresh and a good start!
Wash that cage inside out, with HOT HOT water. Use disinfectant afterward. Rinse everything with HOT HOT water. Get yourself some ordanary gravelstone, or lavastones. Make it a layer of about 2-3cm thick. Put some cocobricks on it, diluted with HOT water.
Squeeze excess water out of it so it is moist but it doesnt drip. Add at least 10cm of coco earth. Remember, moist.. not wet. Place a smaller dish on one end, but not right next to the glass. Get a terracotta flowerpot, shatter it.. dig it into the substrate so you create an entrance of max 3cm higher than the substrate. Dig some substrate right under the tile, small tunnel which it can dig further into.
Place some fake plants, maybe even a smooth rock..
I think you did all that before, but what is new is the backdrop. I have seen most of your enclosures are glass all around. Not that that is bad or deadly, but it is likely to cause stress when people walk around, light falls into it from all corners. It doesn't feel safe. Make a backdrop, foam or whatever floats your boat. Cover one side, the side of the wall. Make it dark, so the environment seems dark to the scorpion.
It doesnt like activity around it's enclosure and this is a way to hide most of that. I think you are very determined keeping them well and I think you check up on them very often. This causes them to never settle. I might be wrong though. But anyway, this is just advice, take it for what it is. If I'm wrong, no problem.. you're doing fine.
Make a lid of plexi or solid material 3/4 the top of the enclosure. Keep 1/4 open for ventilation. In this hole, install a nice and solid red lamp. Let it shine beside its burrow, not straight on it.
It may very well be 30+ degrees in the heat cone..
Keep it moist, don't overdo it though. Wet is not great either. The false bottom will already provide almost adequate moistureness.
This is how my uncle does it and he kept those big [does your mother know you talk like that?] his entire life. I know some Pandinus Dictator he still has, and they date from before my drivers license. Go figure.
If they drop dead when you did all that, then your water is poisoned and you should move for your family and own sake.
Good luck, I'm very sure you will succeed since you got the dedication. Forget about these casualties. A bit of room for improvement, coupled with bad luck.. that's all
Oh ye, DONT BUY ADULTS
edit: ...those big [does your mother know you talk like that?] his entire life...
nope, but she does know I type like that on this forum.
