This would be an easy sale to large companies, HR SaaS apps and especially the gambit of job search sites (Monster, etc). The job search sites can instantly turn this into an up sell.
I want this. I'm in Toronto. If you don't whitelabel, I may never be able to use this :)
How is the demand for software jobs in Toronto?
However, I wouldn't limit your scope to development jobs. This sort of "chat roulette" for pre-screening is a very powerful idea.
Personally, I'd be focusing on the restaurant industry if this was my baby. They spend countless dollars on HR and if there was a way for an assistant manager to sit in an office to pre-screen for real interviews... it would be on fire. Restaurant chain owners are also very willing to spend money on technology like this. I don't think that you'd have a hard time finding low rate, non-intrusive funding from a small group of them to get the entire whitelabel thing off the ground in a hurry.