Its very obvious that anyone will get confuse by seeing 2 station codes of Kalmboli namely KLMG & KLMC. The query is quite expected.
It is really strange but plz note that IRI can't do anything in this regards as Official Site of IR itself shows 2 codes of Kalamboli (pic. 2)
Also, irctc shows 2 codes of Kalamboli. (pic 3)
So, IRI is...
more... following official site & irctc as normally it does.
.
Also, while booking ticket from/to Kalamboli, one has to select KLMG (pic 1)
So, its clear that official name of KLMG is Kalamboli.