Prisoner recruiting?

[Falcon24]

I have a prisoner with a difficulty of 99, but every time I try to recruit, it says 0% chance. My wardens have a skill of at least 10. Is there something I'm missing?

[Falcon24]

Thanks pestilenz!

[Tynan]

There is a chance, but it's being rounded to 0. It may be like 0.2% chance or something.