Remember in the “Prepare to Drop” mission how your squad was preparing to drop?
What happened to the other drop pods that launched besides your squad?
They most likely all crashed landed and found their own ways out, all we know is what we see in the game, there has been no novel mentioning the ODSTs from H3: ODST.
The only other time we seen one of the odsts from H3 odst is when buck briefly appeared in reach the other pods either found their own way out or died.
From what I can gather, ODST casualties after the assault on the carrier, and subsequent EMP blast, were extremely high. Most didn’t have time to react to the emp and simply fell to their deaths, others, like Buck and his squad were the lucky ones. Personally, even though the campaign was epicly awesome, I would have liked to see some more ODST action in the game other than Bucks squad.