You should only withdraw if you think you would be disappointed in the job. Like, if you found out the pay is so bad compared to other jobs that you can get. You are too focused on "if you're not successful" part, but their point is "opportunities with us". If we take this at face value, they mean they want to work with you, and if we take this as a formal thing they say to everybody, they did not mean anything negative. Either way, they were not implying they do not want to work with you.