Default Affiliate for all orders

[MACscr]

I have a part owner of a web hosting company that i run. I guess he isnt really an owner, but he gets 15% of all sales. Anyway, I would like to somehow insert his whmcs affiliate id into all orders processed. Can I somehow just pass his affiate user id in a hidden form input? Any ideas how i can go about this? I have another company with 2 other "partners". I bet i couldnt pass two though. Any ideas how i can handle this?

[MACscr]

Side note to this, how do i make an user an affiliate in the whmcs admin? I dont see that option. The only way i know how to make someone an affiliate is by logging in as the user, the setting them up that way.