Launching EA game via Steam gives error "Game not installed" in EA app
After 2 days and many people having the same problem, someone found a workaround so i'm posting it here in my own question in case someone ends up here specifically with the same issue.
The EA app is currently for some reason unable to find Titanfall 2 installation folder specifically when downloaded over Steam and outside it's own designated folder, and it offers no automatic way to solve it.
Solution is to enter registry editor (win 10 in this case, start-run-regedit) and find this tag: "HKEY_LOCAL_MACHINE\SOFTWARE\Respawn\Titanfall2", and under path type the actual location of the install directory (where your Steam library is, should be something like C\YOUR_STEAM_LIBRARY_LOCATION\common\Titanfall2).
Close the Regedit and the game should be recognized as installed and run.
Another problem i got immediately after i solved this one was some .dll missing inside the Titanfall2 folder that was clearly there, that one is solved by entering Titanfall2/_Installer/vc and running the .exe in the redist folder in both folders you see in there, then choosing to repair.
Credit for figuring registry workaround for EA app bug goes to "Torean0318"
Credit to figuring out the fix for missing .dll goes to "Nightwing3030"
