As with any herb, vitamin, pill etc., most have dangers and/or side effects- some more than others. Both of the websites you listed do not give a duration or a dose for thw Wormwood . You do not know if these are children, adults, what their weight was in proportion to dose etc. As a scientist I would caution you from using the internet as your only source of info for Wormwood , not to say that there may be risks. I am sure if you did the same thing for almost any other product you could find warnings regarding the use of a product. Published jounals (scientific) will tend to have the best and most accurate information, along with dose and duration. It is with this information that you can make the judgement on whether it is safe and/or how the risk if any weigh out.
As for the Wormwood in my parasite program, I have had no side effects, but great results. The program also has me taking a 5 day break every 30 days, and states that there is a danger/risk with long-term use.