Unique Proxy Situation

[Guest]

[timupci]

A brief background. Currently I have ten EFW setup across my organization. They are acting as FW, Proxy and Router connecting to my main location running the EFW. What I am having issues with is the proxy. Here is how it is setup.


MPLS (Blue) -------------|---Main Site EFW 2.5.1 ------------ Comcast 1
VPN (Purple)-------------|                                    |----------- Comcast 2
WrkStation (Green)----|                                    |----------- TPAC
MIS/IT (Orange)--------|

So here is the issue. With the proxy turned off, I can route the different subnet traffic over a specific red uplink. For example, Blue is being routed to TPAC, Green to Comcast 2, and Orange to Comcast 1. However when I enable the proxy, all traffic is defaulted to Comcast 1 (main internet).

I was thinking QoS might solve the issue, but that has issues implementing still. Any hints or tips?