We have a server with a number of users that log on via VNC and use web applications (via FireFox, Chrome or installed apps).
We have several IP numbers. We want all traffic of each different user going though one of these different IPs.
We have iPanel, terminal and VNC access to root user
mark all the traffic generated from one user and route it through desired interface instead default interface.
Document what you have done.
I look forward to receiving your offer and finding a reliable linux admin for future projects (setting up more servers and maintaining them)