Ok. Here's my thing. One is WebMD. Very corrupt website that used to say you could OD on cannabis and it was as addictive as heroine. The second seems anecdotal, and the studies on the bottom don't explain the numbers. What does the liver look like with other medicinal herbs in it like St John's Wart? I'm willing to bet it's the same. I know the AKA actually did a lot of toxicity and comparison tests, and had them peer reviewed, but I no longer have a computer to look at pdf's(using Ps4).
Feel sorry for your friend, but It sounds to me like your friend was mentally addicted like happens with cannabis. I was an alcoholic for almost 20 years, had a bit of liver damage so get tested regularly, and my liver is better than it's ever been after 15 years of kratom use.(I also use milk thistle for it).
Here is the AKA's science page
https://www.americankratom.org/advocacy/science.html I think the report will be in there. The 1st link at the end of the paragraph is a study showing that it is as addictive as nutmeg.
Remember, just like the war against cannabis, there is a current war against kratom. So when researching you have to look for actual science, comparisons, peer reviews. Not just numbers. Google will give you the top results from the DEA narrative point of view. Not trying to be an a-hole, it's the sad state the world is in.
With all that being said abuse of ANYTHING is never a good thing, and it may be that kratom reacts different with different people and can be harmful to those sensitive to it, but I've also seen reports on kratom deaths, and they always leave out the other drugs involved in the death and blame the kratom just like it was with cannabis.
Ok, done hijacking your thread buddy, sorry.