VME klicense must match to the one used for creating PS2 game package. Or else Memory Card will not be found by the game.
As I understand, You want create memory card image with saves for both titles, right? So in such case You must decrypt VME from both games, export saves to PSU containers, import them to new memory card image with ECC, encrypt this vmc to VME format with klicense match to target game.
If You are not on HEN, it is waste of time as webMAN can mount PS2 *.iso and using placeholder klicense for VME (so You can just take VME from one game, and put it to another as i.e second slot (slot is determined by filename)).