this even

Why is Sana still angry with Elias?

Another theory no one asked for:
We still don’t know why the fight happened and it seems like Julie leaves us pretty much in the dark.
The last weeks I was thinking that the fight was about Even as he is the connection between the balloon squad and the boy squad and we know that something happened what seperated them, so it seemd likely that the fight was about Even and his backstory with the balloon squad.

But in today’s clip, something hit me:

Elias mentioning Isak, not Even! So, yeah, it makes sense as Isak was the one who got hurt, if it was by Elias, or not, is still not confirmed. But I think, we can be pretty sure, that Elias was strongly involved as he feels the urge to apologize to Sana (again). 

So why is he emphasizing Isak? Would the fight have been ok, if Isak wasn’t Sanas friend? Or is there more about it?
Even isn’t the only connection between boy squad and balloon squad, Sana is too!!
So, I was wondering if the fight started bc of Sana!- maybe Isak was standing outside with the other boys and was talking about Sana, mentioning her and Elias just heard it and jumped to wrong conclusions. 
We already learned that Sana was heavily mobbed at her previous school, maybe Elias thought it happens again at Nissen… and that’s why the fight started… 
So emphasizing “I didn’t know Isak was your friend” could be important, as Elias now understands that Isak wasn’t talking bad about his sister and that he just misunderstood it… 
And there is something else that didn’t fit with my previous conclusion about the fight: I was really expecting after the hiatus, that Even / Isak might be mad about Sana, bc she invited her brother and his crew but she should have known that this could end in trouble. But they never did. 
The opposite happened, Isak was reaching out to Sana and Even was very happy to see her in yesterday’s clip- would that have been the same, if the fight was really about Even and Bakka? I am not sure.
And it also seems to me that Even and Isak are very chill right now, what doesn’t makes sense to me, if the fight would have been about Evens past…

Well, that’s it so far! I am still not sure how likely this theory is, so I am curious to hear your opinions and if you have something to add, feel free! 

Even can’t do laundry normally and Isak can’t make tea for shit. They’re both messy boys that have The Chair™ where all their clothes are thrown on. They have a wide screen TV to play FIFA on and Isak has an IPhone 7 but both don’t have a kettle and I bet some other basic stuff. They don’t make their bed. They put memes on their walls. They buy a pack of 10 white T-shirts and just both wear them always. Isak doesn’t find his pants? He wears Even’s, which are far too long for him. They aren’t organized at all and can’t remember where they put their stuff. When the other forgets to do something, the other doesn’t yell and just basically says well okayyy whatever while smiling fondly. They both grin like idiots when the other calls as if their crush called to invite them to a movie date. They both say I love you before they end the call. They both don’t know what a goodbye peck is. Only what a slow passionate parting kiss is. The boys are in love and living together. They are a realistic happy healthy couple and no I’m not crying.