I always had the feeling that there were dueling parties during Haley's time on Idol. One partying favoring her, and the other party favoring Lauren.
One of the main differences between Idol and The Voice is that Idol makes money off of it's winner and it's runner up. (Or it used to, I believe the contract has changed after season 11.) Therefore, the show really has an incentive to get the most marketable winner. (Xfactor is different anyway because it's Simon's show..so basically the show makes money off of it's contestants.)
Most likely to be successful has consistently been cute, blonde, female country singer. And my theory on what happened was that everyone and their mother knew that Scotty was going to win. (He was absolutely dominating the votes.) But they were concerned about his future in the music business, and after season 9, Idol really needed a success as a winner. They thought their sure thing was Lauren the entire season. When Haley became a threat (I believe she was running in second place after Rolling In The Deep, but if she wasn't then, she was running in second after Casey left.) they did everything in their power to get rid of her. As we saw with the judges comments. I think this was Nigel's side of the fence.
But I always noticed that in a lot of ways, Haley was treated well. She quite often got "the pimp spot." She did get to sing an unreleased Gaga song. They got Led Zeppelin released for her. She got to perform with her father on the stage. Etc..so someone had to like her. And I think that someone was Jimmy. He was interested in signing her. And he was interested in signing her early on. (When he essentially said to her "You aren't going to win, but show me what you've got because there will be other types of winners.") Interscope had a lot of issues in the way they handled Haley, but I think on the show, Jimmy was on Haley's side.
As for Haley winning..it goes back to what I said..I think Ole is the biggest and best thing that has happened to her. Song writing in pop music is so important, and it's where you get your credibility and make your money. And I think when we look at Haley's career, ten years from now..it'll be looked at as a HUGE deal. I don't believe she signs with them if she wins. So at the end of the day, it might be better off that she didn't. Haley said her gut thought she should come in third, so she's probably right.
As for her being on another show..you never know what would have happened. I'm just confident that The Voice, at least, wouldn't have made played the "Lets see if we can make Haley cry this week" game.