Ok, Found the reward location of the units.

Back: Complete "East Fortress [Apprentice]" Ep 5 quest.

Arm: Complete "Shadow in the city of stillness" EP5 quest.

Leg: Complete "The legendary savior" EP5 quest.

These are all combat missions, and are part of the main EP 5 story. The stuff in between rewards RWB4s and UWBs.

They're also non-skippable parts of Episode 5, contrasting some of the earliest buster quest story missions.

@Miraglyth Which makes me wonder how the previous poster missed these rewards...

This probably should have been posted in general, as it reads more like a question, and less like a suggestion for an in game fix, regarding the units.

@Anarchy-Marine Refer to post #3.

@ZorokiHanuke Oh, ok. Now that makes sense.

@Anarchy-Marine Yeah. I made this thread on one of those never really awake days.

@ZorokiHanuke Everyone's had those days. Usually follows limited sleep, heavy work loads, or both.

@Anarchy-Marine All of the above.