Interference?

[softballaddict]

FED rules. R1 on 3B, R2 on 1B. Less than two outs. (Don't remember but was less than two...oldtimers disease). Batter hits line drive down 3B line. Hits R1 in back/side. R1 was in foul territory. F5 playing near line, behind runner and has glove near where ball would have been had it not hit R1. PU called foul ball / dead ball. R1 goes down in heap. She ends up OK and stays in game. No one objected to call, but I was thinking F5 had a play on the ball and R1 could have been out for interference. Does fair/foul make any difference on interference? I couldn't find anything definitive, but seems to me interference would be a proper call if umpire judged F5 had a play. (He didn't apparently) I know this is HTBT, but would appreciate your thoughts.

[UmpSteve]

NFHS 8-6-10-b The runner is out if she interferes with the FIELDER attempting to field a fly ball over foul territory.

8-6-11 The runner is out if she is touched with a fair untouched batted ball while not in contact with a base and before it passes an infielder ....

No such equivalent rule for being touched by a ball in foul territory.