If we actually look at the Scripture given in the article: "We are "saved through faith," "not owing to works" of the Mosaic Law or of those performed as Christians. Our faith should be more than mere professed faith. (Eph. 2:8-9; John 3:16) It should move us to godly action. [...]
Eph 2:8-9 For by Grace are you saved... not by works... and John 3:16 ...that whosoever believes in him...
Salvation is by faith in the Son of God and nothing else. Acts 4:12 "There is salvation in no one else, for there is no other name under heaven given to people by which we must be saved."
I conclude that by saying "no other name..." that the Old Testament believers are also saved by the shed blood of Christ. There was no baptism for them, only faith in the yet to be revealed savior, Christ the Lord.