By the time Atraks is sent to DSC, Phylaks is long dead, and we have just killed Praksis. Her and Kridis are the only surviving members of the council. It makes sense for her to have stasis at that point and considering Eramis doesn't have a lot of help left. Also, subordinates of Phylaks and Praksis wield stasis in the Glassway. Atraks, even if a secondary member of the council, would still out-rank the other council members lieutenants.

Perhaps, but those Fallen are explicitly disciples of Phylaks and Praksis, who gathered the tech and knowledge to wield Stasis from their mentors. Suck Fallen did not exist for Atraks. The reason we killed Praksis so early on in the first place was to halt his production of the tech required for causal Eliksni to wield Stasis at all. If Atraks, as an isolated, second-rate member, did not have the tech to use a shard by the time Praksis died, she would never receive one. Her title was “The Wildcard,” after all. She was isolated within Eramis’ council because she was an unknown quantity. She took the use of the Darkness in an entirely different direction: resurrecting Taniks and enhancing herself to a purely mechanized form, as a Wildcard might think to do. It seems eminently clear to me that Eramis specifically sent her to do this work in the Crypt as another way to harness the Darkness and ascend the Eliksni beyond Servitor dependence, not unlike the Devil Splicers. She didn’t give Atraks a Stasis Shard because Atraks was already going to acquire abilities of her own, and the direct use of Stasis was already covered by her closer associates.