He succeded in seducing Lind, with her joining in illegal things, causing her to throw her fate out the window and everything good. He tried many times after to convert Supergirl to the "dark side" and actually did if not for his timely intervention, hinting something more.
Over time she continued to save lives and meet people and gaining new powers. This is where the buck stopped for many people. Supergirl was one of 3 Earth Born Angels (Comet , Blithe were the others) fought off every demonic thing that came in their way. And she met god, too. This revelations pushed people who loved kyptonian away from the books. After the trio's defeat of the Carnivore, the first vampire, Matrix was ripped away(or out) from/of Linda. So she had Buzz who was depowered as well and Mary Marvel help her search for Matrix. She found Matrix in Amazon, where Matrix was held prisoner by Lilith, mother of all demons, who had also sent Twilight after Supergirl (holding Twilight's sister hostage to keep her under her evil control). Lilith fatally injured Mary Marvel and Twilight, and Linda, but not before Matrix was freed from Lilith's prison. Linda asked Matrix to merge with Twilight, and Twilight became the new Angel of Fire, and used her powers to heal Linda and Mary, and give Linda the powers she had when they had first merged into Supergirl. And just unlike the current Kara, she met Kara Zor-El from the Pre-Crisis timeline.
But Kara's presence in the Post-Crisis era was going to destabilize time. The Spectre appeared and said that Kara was destined to die. Apparently, a cosmic entity called the Fatalist
had altered the timeline for his own amusement, and to vex his master, Xenon (a being with a pathological hatred of Supergirl). Linda secretly took Kara's place, and was sent to the Pre-Crisis era, where she posed as "Kara Zor-El", until the Pre-Crisis Superman uncovered her ruse, and admitted he was in love with her. The two married, and had a daughter, Ariella. Linda even changed her costume. But Linda's very presence had altered the timeline, so Spectre made her return home, not only to restore the timestream but to save Kara from Xenon, who had captured the young Supergirl and planned to kill her.
So, by many Krypto's standards, this Supergirl was flawed and they wanted Kara....but Linda isnt gone....Fallen Angel screams "LINDA" at the top of its lungs...Later today my favorite Bat