Errors when Taxonomy is chosen in node's Term Reference field
This EntityMalformedException: Missing bundle property on entity of type node errors seems to rear its ugly head in a lot of different contexts. 

In my case it was a configuration of the view that showed the related nodes that had a couple of filters set wrong. 

I had a relationship to related articles, but then in the filter section, Relationship was set to "Do not use a relationship" instead of using the related article. Setting the correct setting on the filter fixed the issue.