All IMHO - From the beginning there was and is an assumption that K and M were BFFs. They may have been close, longtime friends woven into each other’s families, loved each other dearly, but not really BFFs.
They pledged different sororities. IMO, that is a big deal. Close like a family ‘sister’ is very different than the secrecy between sorority ‘sisters.’ K and M, by sorority definition, had to have many secrets from each other.
All IMOO. Source - life experience; lived and worked in the collegiate Greek system, assigned to many campuses in many states.
Sororities and fraternities are extremely private and incredulously secretive and confidential beyond understanding unless you experience it. Huge secrecy in Greek life, with loyalties, rivalries, territories, intricate social and ritual details. Greek life is not one big group. Each specific organization is unique, a subset of Greek life, with its own associated internal/external/local groups/friends. Generally each is a ‘chapter’ of a national organization, like Elks or Moose lodges, except the members are fulltime students, young, and sworn-in for life.
This crime has a subculture unknown to most people. This case may not be about the friends’ closeness, but the gaps between them, JMO.
Just information: House occupants included 3 (M,X,B) in same sorority, M was B’s big sis, and 1 (K) in a different sorority. E’s sister is in another different sorority. E and brother/H were in same fraternity. The young men associated with the housemates, IMO, appear to be associated with a different fraternity. An accident earlier this year was the eve of an event for that fraternity. Who was there? Are/were JD or A in a fraternity? M’s BF? Did anyone quit a sorority or fraternity recently? Are any of the chapters on campus on any kind of ‘notice’ or warning? Many IG, venmo, activity with variance and Greek nuances. The 6-degrees from crime to assailant may be between who is known, details of interview, evidence, all the technology accounts, social media accounts, calls, texts. How are they connected or disconnected and where was loyalty damaged?
If the assailant feels justified, then he could have acted normal when entering and leaving, and continues to act normal. So, who is acting differently? Who can, but can’t talk? Who was where, when, but wasn’t? Who was with whom, but wasn’t? Who told whom, but didn't? ...
Not my theory, just sharing thoughts for consideration. All IMOO. BBM