KRCL has 2 pitlines at MAO even those are underutilized forget about building new ones at Thivim. Also it is much better to commission 2nd pitline at Vasco Da Gama which is nearly done but works stopped since last year and then extend some trains rather than developing new pitline at Thivim.
See how many trains undergo PM and SM at MAO on 2 pitlines with automatic coach washing facility and compare that with VSG with a single pitline and no automatic coach washing. You'll get the answer.