The Airfoil Video Player is just an .app thats inside of the Airfoil.app bundle. You can add "$AIRFOILPATH/Contents/MacOS" to your Alfred "Search Scope" (Settings, Features, Default Results) and you're done.
Another option is to write your own simple Workflow:
+, Templates, Essentials, Keyword to Applescript Choose your keyword (no arguments) set applescript to
on alfred_script(q)
tell application "Airfoil Video Player"
set test to track title
end tell
end alfred_script