Tragically The Inventor was an inventor (which was why he called himself The Inventor) rather than a salesman. If he'd been a salesman, he would have mentioned to Lionel that Edward was designed to live forever. Immortality - that would have been a selling point to interest Lionel. Of course, as you probably know, immortality isn't easy to achieve - it usually takes forever - and, in order to achieve it, a set of nanites were on constant vigil throughout Edward's body performing any necessary repairs.
It was thanks to these nanites that, by the time Edward had used his scissors to claw his way to the car holding Lex, feeling was already starting to return to his legs.
As he clawed his way onto the car hood, he saw Lex sitting there unconscious, peaceful, with his inhaler floating next to him. Once upon a time, Edward would have been no use in this situation, but all of his years with Martha and Jonathan had taught him not to panic. Sure, this was going to be difficult, but it could never be as hard as milking that cow.
He drove his scissorhands into the shoulders of Lex's jacket, managing to avoid Lex's actual shoulders, and then used his bodyweight to lever Lex out of the car. Then came the difficult task of dragging him to the shore. Time was of the essence, but Edward's legs were not yet fully repaired, so, quicker than any human could, he walked on his knees to the shore, dragging Lex behind him - fortunately the jacket was well-made and managed to survive the journey intact, which was more than could be said of Lex. By the time Edward had managed to claw Lex and himself up to the shore, Lex was no longer breathing.
At which point, Edward decided to attempt mouth-to-mouth resuscitation. It took a long time, but Edward didn't give up, and finally, as he was kneading Lex's chest one more time with his elbow, Lex coughed up a mouthful of river and started breathing again.
By the time Lex opened his eyes, Edward's scissorhands were back in their pockets (he'd have to dry them soon - the nanites didn't protect the scissors and he didn't want to risk rusting).
The mud-drenched Lex, with his shock of red hair, looked at Edward kneeling next to him and a look of horror filled his face as the repressed memories finally came flooding back.
When Edward saw that look of horror, he realized that Lex would never forgive him for what he'd done all that time ago. So, saying nothing, and with a great sadness in his heart, he stood up, turned around and started limping away. As the nanites continued their work, the limp quickly became a walk and the walk quickly became a run.
Lex sat there, feeling the cuts on his lips, noticing the holes in his jacket.
"Scissor hands," he said stunned. After all these years, he'd begun to think that he'd dreamt it all. All those years of fears, afraid to walk outside alone, afraid to have a haircut ... and those fears were all because of one man. He remembered the lecture that his father had given him countless times. It was time to stop being afraid. He could never do that before - all his fears were internal - but now things had changed. Now, somewhere in Smallville, his fears were walking around with a white face and black hair.
It was time to conquer his fears. It was time to reclaim his life after all those wasted years.
While Lex sat there, making his plans for revenge, the paramedics arrived (he asked them who'd made the call, but unfortunately his nemesis didn't leave a name). Once they'd checked him out, and put some antiseptic on his lips, they offered him a ride home. But he refused. He walked home alone, for the first time in so many years. Where there had once been fear running through his veins, now there was vengeance. It was a new Lex Luthor who walked home that day. The old Lex Luthor was dead.