You can defer the 5k, or the 26/10K, or both. If you do it pays out after you would no longer owe it back if you left. So 5K pays after first year (I think) and it’s yours to keep. The 26 plus 10 pays 3K per month from month 13-24. Again you get it as it’s “vested” so each 3K is yours to keep.
Defering, as I see it, has two advantages. Tax savings by spreading bonuses out over two tax years, and leaves the door open to leave before 24 months if you get a better option. Seems like a good option for the military folks that tend to get picked up faster.