It seems very unlikely that the lock maker would have any record of the combination. And if the previous/original owner did their “due diligence” the combination is supposed to be changed by the owner upon receiving the safe. Some safe makers (most?) will set a random combination before delivery.
One choice would be to find a locksmith who can either manipulate the lock open, or drill and repair. Try http://savta.org/ and click on “Safe Tech Search”.