You are right. There is no conclusive way to tell a suicider from a person waging war. I wish this didn't even come up but when you have under 100 active players and 5-10% of them are suiciders it will come up pretty often. Especially when it is so easy for 1 person to do it three times in a set.
This may or may not have been a suicide. In my eyes a suicide is a war that has 0 end game for the attacker. Had we been farming this tag then they would be justified. Had we done unsolicited war attacks they would have a reason. There can't be any ingame reason for their attack as we didn't even know this two states in hiding existed. They have no hope to gain anything from this war. Even if a smaller tag wars a bigger tag for a reason and knows they will lose, they at least gain respect and stand up for themselves. Such was not the case here.
Also no action needs to be taken against these two states since the fast action by CR lead to their deaths almost before I even knew anything had happened.
It isn't the rules of the game that need to change it is the mentality of the players. I don't know how to make that happen so I fear for the game when over the last 5 years people have shown absolutely no growth in maturity. Kinda makes me feel sad as a human to see that as well.