Counterpoint: I've won recruiting battles where I didn't knock off the Sim, but still eventually signed them.
The key lies in having a big enough lead that you sign the recruit before the Sim can put in enough automated effort to flip the recruit to considering them. It's complete guesswork, though.
For this time, you're just going to have to cross your fingers and wait. For future instances, knock Sims off fast and early. Don't leave your signings to that kind of chance.