Sad to say, your friend should have done a LOT more research before jumping in to buying a snake he knew nothing about.
Anyone who knows anything at all about spiders knows they have this issue, and that any morph carrying the spider gene can have it too. There is a ton of information on the internet on this wobble, and hundreds of videos on YouTube.
Now, this snake is underweight at the moment, but it's obviously eaten before or it wouldn't be as big as it is. The first and most important thing is to get rid of those mites. You freind needs to get on Ebay and buy a can of Proven-a-Mite and have it shipped to him. In the meantime, he can soak the snake every day in lukewarm water with a single drop of shampoo in it to break the surface tension on the water and help drown the mites. This IS NOT a permanent solution, just a temporary one until the Provent-a-Mite shows up.
The snake needs a warm, quiet place to rest and as little handling as possible. Your friend should not offer food for at least 5 days of minimal disturbance of this snake. This animal will always wobble to some degree, however once the stress of mites and moving subside, it should improve. There is no reason for this animal to die unless your friend let's it die.
Send your friend here to read and learn all he can, treat the mites and allow the animal to rest and de-stress and it should be fine.
Gale
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