Overthrow

Question
I have an 8U Fastpitch Machine Pitch team. My question is in reference to Rule 16 #8 on page 59 of the USSSA Fastpitch Rules. On a batted ball, if a fielder overthrows the first baseman, the ball remains within the playing field and no other attempt is made to throw to another base, is the batter/runner allowed to advance all the way to third base if possible or would they be required to return to second base after the play is called dead?
Response
Rule 16.8 states One base will be allowed on any type overthrow.

It does not matter if it is live ball or a dead ball.
The runner would be placed on second.

We protect to second. They are frozen on second.
The play should be dead when the runner reached second unless they have a runner scoring.