A little investigating of the plant(s) will help. Often Podocarpus are sold with multi plants growing close together for a quick thick looking shrub.
Looking closely at the base of the Podocarpus. Do you see multi trunks coming from the ground or do you see a single trunk. If multi trunks are found follow the trunks to see if the dead branches are from the same trunk.
I learned from experience that a problem often with the multi trunk Podocarpus plantings is often the survival of the stronger plant taking water and food from its competition.
No fear if you find this to be your case. It will take a some time but the survivor(s) will fill in the area left from the dead plant.
Keep in mind Podocarpus are really trees. Do you know the variety of Podocarpus you are growing? Some varieties grow very large and not well suited for tight spaces.