That doesn't rule out the possiblity of assistance coming from anyone in Malaysia, someone could have helped them in any number of ways, perhaps letting them carry weapons onto the plane. What it does mean is that the Malaysain government as a whole was not in on the plot. The timing of events, turning off the transponder in that overlapping area between airspaces was, IMO, meant to buy the hijackers time to get the plane out of the area while Malaysia and VN ATC's were like :waitasec:
bbm
Just another thing the hijackers would have to have researched/knew somehow.
This seems to be very, very well-planned and planned far in advance, perhaps spanning years of planning.