Currently we just call the NorthstarLauncher.exe binary. This means however that some prerequisites need to be met for Northstar to be able to launch successfully such as Origin already running for LSX authentication to function.
If we instead could just do something like steam://<Titanfall2 App ID> -northstar (where -northstar would be passed to the Titanfall2.exe, and then in turn caught by our wsock32.dll to launch Northstar), we could skip all the prerequisite checks and also get Linux+Steam support for free.