You will find the original source of the waypoints Vampi, Gival and Igrex in this Reuters article, only quoting "sources".
Exclusive: Radar data suggests missing Malaysia plane deliberately flown way off course - sources | Reuters
But it does tie in with the Malaysian Prime Minister's address on STurday in which he stated that Malaysian primary radar tracked the plane to a point north west of the Malacca Strait.
Today the New StrIts Times gives the last tracked position as being 320km north west of Penang.
MISSING MH370: 'Plane flew low to avoid radar' - General - New Straits Times
Hope this helps.