Thats kinda scary. A bushbaby is a completely different animal, its a small primate if I'm correct.
If he didn't even know what the animal he has no business keeping it. Atheris, particularly the larger varieties (squamigera, chlorechis, nitschei and desaixi) have pretty potent venom ounce for ounce and there have been recorded fatalities from bites. Furthermore, there is no AV.
Anyways, good luck with your chlorechis, they are fairly easy to keep. The main thing I've noticed with mine is that they require daily misting to keep them hydrated properly. Mine won't drink anything other than droplets off of leaves. Also, as adults they don't require much food, and get overweight easily. Sorta similar to Waglers really.
You may have found this already, but the link below is to a good site on the various Atheris sp.
Eric
Link