Going twenty or so minutes back to the past when those new Space-Time Units just appeared...
Ever since Rean returned from the sect with the elders, he had not been present in any of the battles. In fact, the only time he appeared for the SANS Units was when he arrived with the sect several months ago and then made his escape with his group. Above all, Rean's Domain was pretty useless in this place, so his presence, even though he was relatively strong, had never been considered that dangerous compared to Roan and Celis.
The reason he never appeared in the attacks was simple, he was back in the CAU Units headquarters, working on the new device with Zangeshu and the CAU robots. So, he didn't have time to help Roan there, but it also turned out to be a good thing.
