Runner's Lane Question

[Manny A]

I have a question regarding when a batter-runner takes that last stride into fair territory in order to touch first base in organizations that use just the single white bag at first. The question is: Is it different when the BR stays completely in his/her runner's lane until he/she must exit it to touch the bag, versus when the BR is outside the lane?

Here's what I mean. In pro baseball, the BR is given leeway when he stays in the three-foot lane on his way to first, but then hinders the fielder at first base taking the throw when he steps out of the lane "in the immediate vicinity of first base for the sole purpose of touching first base". "Immediate vicinity" is defined as the last step or stride before reaching the bag.

But if he's in that exact same position without ever having run in the lane (e.g., he's a righty batter who bunts the ball, and runs all the way to first base completely in fair territory), that leeway goes away. Any hindrance with the fielder taking the throw at first is treated as a violation because he never properly ran in the lane.

How is that handled in softball? With the NCAA reestablishing the runner's lane rule for next year, they included the exception that a BR may run outside the lane "if she leaves the lane on her last stride in order to touch first base." So do we treat a college softball player the same way as umpires treat BRs playing under pro baseball rules when it comes to being in fair territory for that last stride before reaching the bag? What about in NFHS or other softball rule sets that allow for a single first base bag?

I actually had that happen to me in a college scrimmage last Friday. The batter bunted a ball a foot or two up the first base line, and took off to first, basically straddling the foul line. F2's throw to first was right on the line, and F3 could not see it until it passed the BR a step or so before the BR reached the bag. If the BR had been in the lane the whole way until that last stride, I would've said No Harm, No Foul. But because she was never fully in her lane, I ruled her out for the violation. The first base coach insisted first that the ball didn't hit his BR, and then argued that she had to be where she was in order to touch first base. But I told him the BR never stayed in the lane to begin with.

Did I rule correctly?