it was confirmed that krieg is not tinas father. in an interview it was stated that before hyperion experimented on him krieg was a former bandit who became a vault hunter. this does however leave the possibility that krieg helped tina escape after she used the grenade her parents gave her.
i believe this is said interview. http://www.youtube.com/watch?v=khmi49sfecg --- PSN: demonofsparta. SSF4AE--Oni. JJBAHD--Dio Brando. UMvC3 team--Haggar-FF3, Hulk-Green King, Akuma-.Cyber Akuma white2 FC 3526-0179-9641