@gg1998, you are asking some very specific questions of @MeiTanteixX we don't have the information to answer. Right now we are in the "nice story" stage of making inferences about the plot because we have some info, but not enough specifics to rule things out. The best we can do is come up with simple ideas that are consistent with the evidence. @MeiTanteixX's version of events is quite reasonable and pretty consistent with what we know, although it is hardly the only reasonable tale that can be spun. You should at least be able to acknowledge that much.
@gg1998, in my opinion you are premature in most of your arguments. You jump to conclusions like "Rum posed as someone very close to Amanda to get the access to her and circumventing Asaka" and think "Rum was able to easily dodge Asaka but wasn't so lucky with Haneda's murder" is illogical, but you haven't really justified any of that with evidence from the storyline that we know. We simply don't know who was where at what times and thus who was defended and who was undefended when things went down. The evidence of a good argument is that it constantly refers back to the source material.
Finally, the personal attacks you are making (e.g. "you miserably ignore the point", "You just being another primed person is trying desperately to think Haneda murder as collateral damage you don't consider that it could have been the part of the plan.") are unnecessarily demeaning. Cut that out. You can be civil with someone you disagree with.