The proper response is, "Show me the prestige class, and I'll decide whether I want it in my game." This is true of prestige classes from the internet, from 3rd party publishers, and from WotC books.
To ask whether you will allow it before EITHER of you have seen it indicates one of two things: 1> He's stuck on the name and really couldn't care about the rules or 2> He's got an inside track on the information, and is afraid you won't allow it after you've seen it.
In case 1> you risk -strongly- having him change his mind once he's seen it.
In case 2> you risk putting a prestige class you don't like in, sight unseen.