Updated setup :
Router 1 (College Campus) : 10.1.0.1/16
Router 2 (ISP Router) : 10.1.0.4/16
Both Routers connected to each other. Hence R1, R2, pfSense WAN on same layer 2 network.
pfSense :
WAN 1 : 10.1.0.2/30 Gateway : 10.1.0.1 (Default Route)
WAN 2 : 10.1.0.5/30 Gateway : 10.1.0.4
LAN 1 : 192.168.1.1/24
Firewall Rules for LAN :
Alias containing FQDN of all websites :
6b96fa66-776e-4ff8-bbe7-aedc38148776-image.png
LAN Firewall Rules :
3afd9723-cda6-4f17-aa55-6f24bb65fd59-image.png
Traceroute Diagnostics :
8e909d0a-e047-4a0a-b12c-790c0c05c888-image.png
Results :
e5319961-1ec7-4e52-aa9a-b74a76de46e9-image.png
Test (if BlockedWebsites firewall rule is disabled)
b0c5d34f-029d-4947-a6a8-1741f6e7d4af-image.png
So yes, I believe that Sophos ( the firewall which my campus uses) blocks access to the TLD name, hence blocking any chance of redirect. So I guess I was partly right in saying that Sophos can't really block CDNs since many websites originate from the very same CDN.
Also, I still can't understand properly what causes so much trouble if both the gateways are on the same subnet.