Overthrow

[SRW]

Just wanted to post this situation that happened to me last night in a co-ed slowpitch game, to make sure I called it right.

1 out, runners on 2B (R3) and 1B (R4). B5 hits a can of corn to F7 - B5 out. R4 forgot to tag, and runs to 2B. R3 tagged, and took off on the catch to 3B. The throw comes in to F6. The base coach is screaming at R4 to go back to 1B. R4 realizes what she did wrong, and busts back to 1B. F6 throws to F3, but F3 misses the throw, and the ball goes into Dead Ball territory past the fenceline. I signal dead ball. R4 then makes it back to 1B.

At the time of the throw, R3 was on 3B, and R4 was heading back to 1B.

My question: would B3's "last base touched from the time of the throw" be 1B or 2B? I took it to be 1B. If it was 2B, then I should have awarded B3 home...

I awarded R3 home, and R4 3B. I allowed R4 to complete her baserunning responsibilities by tagging up, then awarded 2 bases from 1B. Did I call it right?