I don't see what conceivable ammo it could give Trump. HE is the defense. The Daily Kos has nothing to do with him, or he with them. They didn't use some kind of wizardry to figure out the redactions. All but one of the CCs had already been identified. Anyone could have figured out who they were. They have, after all, appeared in other cases. Some have been criminally charged. Some of the witnesses, like Jenna Ellis, have also been criminally charges; she's pled guilty.
Many other witnesses are easy to recognize. We all know who the governors of Georgia and Arizona were, for example. Not to mention Tucker Carlson. Lots of familiar names.
And I imagine the AI Guy identified some of the witnesses through footnotes citing articles in which they were featured.