conflict between and a friend and employer

I agree with Iab. You need to stay clear of this. Treat it as though you made an introduction and that is it. But if you get further involved you risk loosing your friend or your job or worst case both.

Without a contract in place or even any formal quote or proposal I think your friend will have a hard time winning and it will be a substantial hassle for your boss even if he wins so expect some grumpy people at the conclusion.