The D'Zidran was an Alliance vessel under the command of Commander Tal in the alternate timeline where Montgomery Scott rescued James T. Kirk before he could be absorbed into the Nexus.
In 2283, Tal met Guinan on Alliance Prime, who warned him of poor repairs to the Cormier, saving them from certain vaporization. Although the Cormier was later destroyed, Tal allowed Guinan to accompany him in his subsequent commands, including the D'Zidran.
In 2293, while leading a fleet of twelve Alliance vessels, the D'Zidran was the first vessel to intercept the USS Enterprise-D, which had followed Scott back in time through the Arhennius system. The alternate Guinan helped convince her commander that Captain Jean-Luc Picard and his crew were not agents of the Borg Collective, but Tal was still surprised to be speaking to Terrans after the Borg assimilated Earth centuries prior. Tal consented to rendezvous the D'Zidran with the Enterprise and allow Guinan to transport aboard.
Once aboard the Enterprise-D, Guinan spoke with Captain Picard and her counterpart on the Starfleet vessel and was able to learn a great deal. Guinan asked Tal to issue a fleet wide search for Montgomery Scott, which proved fruitful when he and Kirk were found on the Wisdom with Supreme Arbiter Sarek.
While the Wisdom and Enterprise-D met and dealt with potential Borg spies, Guinan convinced Tal to take the D'Zidran ahead to Gateway and find the Guardian of Forever, where Guinan learned the source of her powers and how to return the timeline to the one the Enterprise-D crew knew. When the Enterprise-D succeeded in returning the flow of time to its proper course by returning Kirk to the Nexus, the D'Zidran ceased to exist. (Star Trek novel: Engines of Destiny)
