Wesker wasn't exactly trying "Restore Umbrella" though...He was the WHOLE reason Umbrella fell...And he planned it like that...Before he realized his plans to become a god...he wanted to start a new "Umbrella Like" company if I remember correctly...not Umbrella itself...I could be wrong, but it seems like Krauser was focused on Umbrella itself, going so far as when Leon asks, "Why do you want to restore Umbrella?" he replies "To bring balance to this crazy world." Basically what Wesker wanted too, but Wesker didn't want to restore the ACTUAL Umbrella Corp...