Adding the Sauce Connect binary into our infrastructure is possible but creates additional overhead. For security & maintenance reasons new hardware/deployments must be configured. This adds to the overhead of our already functioning Sites Under Test.
Adding new infrastructure also increases complexity and adds another failure point that must be investigated. Aside from the binary itself our Site(s) Under Test must be configured to use any new access points. This could mean extending a virtual cloud or local network, adding new deployment steps to the Site Under Test, or relying on other teams to make configurations on our behalf.
If we could whitelist a single subdomain, IP address, or a limited address range that would solve the above problems though. Whitelisting is already an accepted solution but right now we can't guarantee all traffic is from our tests. If a dedicated endpoint was added just for our organization we could safely whitelist and start testing right away.