We need more details here. You say his route got eliminated. Are you getting any of the "junk" stops that were thrown on him? Where I'm at his route has to be eliminated for 30 days to bump permanently. Before the 30 days he can follow his work if it is split up between more than 2 drivers and has seniority. If split between 2 drivers he has to follow where the most work is if he has seniority. If you get bumped permanently you should be able to bump any less seniority driver. We are given only 3 bumps, and after the 3rd that person is SOL (unassigned).
Talk to your steward for what your options really are.