Actually MCServer already has a StringSplit() function that does more or less the same thing, but may be faster because it's native. It returns an AStringVector, which is exported to the Lua API so that you can use:
Not sure now if the arrar is zero-based or 1-based. But you already use that because it's how commands are handled
Code:
local Values = StringSplit(IniFile.Get(...), ","); -- split by commas
local First = Values[0];
local Second = Values[1];
-- etc.