The reason the Time Manipulators did not participate during the Chaos Immortal's attempt to invade Vale's Shadow Domain was due to the task given to them.
Apparently, they were bound to a mission that could not be disturbed. Any interference might have cost them their lives.
This mission was not one of battle, but of discovery.
Vale had entrusted them with a task that required patience and secrecy. They were to search for a lower realm, one that could be exploited, and hopefully, this would eventually elevate their current realm into a higher plane under Vale's influence.
Vale had not learned this from the Shadow Realm itself, but from the Time Manipulators.
They alone understood the delicate requirements for a realm to ascend. Among those requirements was the Will of the Realm itself.
