Ian, Anisa, and Hassan are all childless hedonists so I don't expect them to understand this, but it bears mentioning because Anisa obviously reads the thread.
Ethan and Hila's explosive anger after the CPS visit was completely justified and actually convinced me (someone who dislikes both of them) that they are probably pretty good parents. Parents SHOULD become unhinged the moment something effects their children. It was incumbent upon you, as a friend, to do whatever was necessary to help ensure the safety of their children (AKA the single most important thing in their lives). Your job, AS A FRIEND, is to help your buddy when things get tough even if it feels performative. And I can't imagine a more distressing situation than thinking your kids could be taken away.
If Anisa and her husband were truly empathetic, they would have noticed why Ethan and Hila were being so vitriolic. It's important to note to these armchair psychologists that rage is not a "bad" emotion. It exists for a reason, and there are situations in which it is appropriate. One of those would be protecting the people you love.