Well on that 1st pic from Mobygames it says (c)1998 Interplay Productions.
So yeah I think it's launch day 1998 edition of the game. Same with soundtrack CD. It has a visible (c)1998 thing.
Layout and artwork is very similar to
the 1st Fallout, so I think this CD had a similar fate of being included with certain copies of the game. (maybe with the very first batch print)