Inadvertent Whistle & Lane Violation Question

[South GA BBall Ref]

Just thought that I'd get the opinion of the forum on this play.


CASE PLAY

A1 has the ball for one free throw.
Before A1 releases the ball, B1 steps into the lane.
The official inadvertently sounds the whistle instead of simply showing the delayed dead ball signal.
A1 stops the motion and does not release the ball.
The Lead Official gets the ball from A1 and re-administers the free throw.
A1’s free throw is unsuccessful.
The officials allow A1 another free throw because of the violation by B1, which caused the inadvertent whistle.
Are the officials correct?