Hahaha, oops. I totally forgot about that part. If he's nearby, would he feel and or sense it? If he's scouting near the Terminal, he'll definitely recognize our auras.
Speaking of which, does a magicians body, when the magician is out projecting, have an aura on its own? If so, he would definitely recognize his own body sneaking up on him.
Sorry about that; attribute it to Marcus' inexperience with Magic, which is incredibly but accidentally appropriate...