Looking at the 1929-30 goaltending records one will find the Maroons record showing 14 games for Benedict, 1 for Cox and 30 for Walsh, for a total of 45 games in a 44 game season.
Going through the newspaper accounts, one gets 14 games for Benedict, 1 for Cox and 32 for Walsh, for a total of 48 games.
In the November 30th game Benedict took sick and left after the first period, with Walsh playing the last two periods.
In the January 7th game Benedict was hit by Morenz's shot at around the 10 minute mark, and Walsh played the last 50 minutes.
But in the March 4th game the time that Benedict is injured is "shortly after Kilrea's first tally", or shortly after 4:35 of the first period.
I'm wondering if anyone has a more definitive time than "shortly after"?