[Kailo]

1) This is not required in latest CS:GO dedicated server version 1264 (if yours 1263, just update it. Valve already fix this by removing/changing this part, don't look how)
2) You don't need to change sourcemod.vdf because it loaded by metamod, not by the game and have another algorithm for this (but similar)
3) For linux64 binary must have "_client.so" extension. So, you need to rename binary from "server.so to server_client.so" and use "addons/metamod/bin/linux64/server_client.so" path