I wonder if they said it was targeted simply because the other two roommates were left alive?
True, but in relation to that, and bear in mind I'm still catching up, so not sure if it's been confirmed where everyone was, particularly with NG saying surviving students were on 3rd floor and other reports saying 1st floor.
I'd say the surviving girls were 3rd floor bedrooms and the perpetrator didn't know they were there or was spooked in leaving which is why they weren't attacked.
The rest is just MOO and absolutely not based on anything other than my thoughts at this moment, but for me, it makes more sense that KC and MM were 1st floor bedrooms. Entry to the property via front door, could have been easy, particularly, if as reports say the key code may have been well known.
If the perpetrator entered through 1st floor door, they'd have KC and MM in their own respective bedrooms (just because they both called someone whose name began with the letter J, doesn't mean it was the same person, so, in my head MM was calling her boyfriend J from her room, and KC was calling another person whose name began with the letter J from hers) - I don't think they were together in one room, would imagine it was blitz attack on one and once finished there move too the next room.
Once finished there, they make their way up the stairs, but, by that point I would guess Murphy would possibly be barking, so either Ethan or Xana came out to let him out thinking thats why he was barking, and the perpetrator came across whoever let him out (i believe this would most likely be Ethan and which, in my head, would line up with friend making 911 call following day about someone being unconscious - there is a chance they could possibly be seen from sliding patio door from the outside, hence 911 call being made), then I think the other half came to see what was happening as its taken longer than expected to let Murphy out and they got attacked - I believe this would most likely be Xana because her Dad said she'd put up a fight. The fight, may have been enough to make the perpetrator leave - by this point there's been a dog barking and someone resisting you, if they screamed/shouted - that could be enough to make them leave, which would leave whoever was on the 3rd floor unharmed physically.
I think one or 2 of them were targeted and I don't think it would have been Ethan.
Like I said, just my thoughts and moo, so please don't shout me down everyone lol - its been a crappy week, and it's just one of a gazillion thoughts about this going through my mind. At this moment, this makes the most sense to me, after I've caught up on thread - I would have probably changed my mind a few times!