I am so sorry to hear about your lab; some snakes do have
venom which can cause massive bleeding, and in googling South African snakes I found the following info:
Boomslange and Vine Snakes inject Haemotoxic venom which destroys the platelets in the blood and causes major internal bleeding in the lungs, liver, kidneys, spleen etc., and blood will also leak out of all orifices in your body, including minor wounds and bruises.