I am wondering why the love route is mentioned in the walkthrough. The parts after it don't mention anything about a love route, and I have only ever seen the exact same scenes / behavior from her over numerous playthroughs.
Usually I corrupt her to 10+ before I put her in chains and bring her Lyvia, then I raise her affection to 10+ before going to get the camp / save Lyvia.
Then I only have sex with her once at the camp, and she is willing to help the party. First time I invite Tia to bed and make Imawyn up, Imawyn leaves the tent. Second time she joins in.
If a true "love route" exists, I think it just minute dialogue differences with the exact same scenes / behavior from her.