In the FAQ 1.1.6: The Death of Asmodean writen by Karl-Johan
Norén, Kevin Bartlett, Pam Korda, Leigh Butler Sammael is rejected
as a suspect because of a remark made to Greandal;

".......kill Asmodean? I would if I could find him, but he has
gone over to al'Thor. He's teaching him!" This is in a Sammael
POV section. He is also trembling with anger, which makes it
quite unlikely he's feigning ignorance of Asmo's fate. Thus, it's
unlikely that Sammael did the deed.

This reasoning is flawed because;
Sammael makes the remark.
Greandal comments.
Sammy gets angry.

".......kill Asmodean? I would if I could find him, but he has
gone over to al'Thor. He's teaching him!"

"Always some excuse for your failures," she whispered
into her punch, again too softly for him to have heard
without Saidin. In a louder voice, she said, "Choose your
own explanations, if you wish. You may even be right. All
I know is that Lews Therin seems to be removing us from
the game one by one."

Note that in the first paragraph of the chapter:-
Cautiously Sammael stepped onto flowery silk carpets,
leaving the gateway open in case he needed to retreat, and
*holding hard to saidin*.;
and in the ninteenth paragraph:-
He let the gateway vanish but held on to saidin: those tricks
did not work on someone wrapped in the Source.
Then in the third last paragraph of that scene:-
She shrugged as though it did not matter, but her lips
moved slightly, and his saidin-enhanced hearing plucked
"If you are still there" from the air.

All of this tells us that Sammy held Saidin the whole time and
therefore heard Greandal's whispered remarks, remarks
guaranteed to anger Sammy. While he may have been angry
at the thought of Asmo as teacher, it is Greandal's remark
"Always some excuse for your failures."
that truly enrages Sammael.

If Sammy was not angry when he implied he could not find
Asmo, he cannot be eliminated as a suspect.

Therefore, the most likely killer of Asmodean would have to
be Sammael.

Since rereading the FAQ I am very inclined to agree with the
"Accidental Discovery" section, Sammy wanted to get Rand
while he was occupied with Rahvin, but had to be satisfied
with Asmo.

maj