What's a "shallow attempt" to field a ball?
If it's an attempt to field a batted ball where the umpire judges there was
no possibility of an out being made then this isn't interference.
If it means making some move toward the runner that's not part of a reasonable effort to make a play, but designed more to draw contact and a call that wouldn't have otherwise been there, then that's not interference either.
But if the fielder had a legitimate play and was simply trying to make it, then this is interference. It doesn't matter is the runner
tried to avoid contact or if the runner had any idea where the fielder was playing or moving. Those aren't requirements of the playing rules.
If a fielder is in the act of fielding a fair batted ball and a runner impedes that effort and prevents a play, then that's interference. The fielder has the 100% right of way here. Runners are obligated not to interfere, whether accidently or intentionally.
Correct ruling? Interference, dead ball, runner out.