Game Situation: Runner's Interference?

 
With one out and a runner on second base (R2), the batter (B1) hits a pop-up into the middle of the infield. R2 runs back to 2nd base because he is worried that one of the infielders may catch the fly ball and double him up.
 
R2 is standing on 2nd base when the infielder runs into R2. The infielder falls down and is unable to catch the pop-up. R2 remained at 2nd base and the batter safely made it to 1st base.
 
Is R2 out for interference? Or is R2 protected because he is standing on the base? Is B1 out because the infielder probably would have caught the pop-up? How about calling both out and ending the inning?
 
Bonus Question:
As R2 stands on 2nd base, the pop up hits him just as the infielder was prepared to catch the ball. R2 remained at 2nd base and the batter safely made it to 1st base. 
 
Is R2 out because he was hit by a batted ball (even though he was standing on the base)? Is B1 out because the infielder probably would have caught the pop-up? How about calling both out and ending the inning?
 
Call
On the first play (the fielder runs into R2 while R2 is standing on 2nd base), the runner is not required to vacate the base in order to permit the fielder to catch a fly ball in the infield (as long as the runner does not intentionally interfere) -- NF 8-2-8. So on this play, R2 can remain at 2nd base and B1 can remain on first base.

I found a video of this play at 3rd base: https://www.facebook.com/video.php?v=907934382570318&set=vb.100000612942862&type=3

On the bonus question (R2 struck by a fly ball while standing on 2nd base). The base does not protect the runner from being called out for being stuck by a batted ball while the fielder is in a position to make a play on the ball. So on this play, R2 is out and B1 can remain at 1st base.