Coming in to this one a bit late, but I agree that:
There was no play, hence there can be no interference,
The situation is not specifically covered in the rules,
The offense should not benefit from this action, and
Using 10-1 to apply 7-6P-S Exception, dead ball, no run, runner returns is the best/correct ruling.
But, it does occur to me that the interference / out ruling would probably be the call expected by both coaches! 😉