You are taking on a hell of a challenge, but, that is what makes a challenge a challenege.
There are so many ways to take it on. I would suggest you prep yourself to spend a lot of time on google searching for "vocal removal software"
The problem is there is no one way to do it and you will get varied results. Adobe Audition seemed effective, but it was not a complete solution for me either. It may work for you though and your needs.
The site www.ltsound.com is a hardware based vocal remover and seems to be the best on the market, but costs more than the would be software equivalent.
Good luck with it.
Before you criticize someone, walk a mile in their shoes. That way, if they get mad at you, you'll be a mile from them and they'll have no shoes.