The 2022 Olympian had the third fastest opening run in 54.27 seconds, and in the second run had the fourth best time in 54.42.
Her two-tun combined time was 1:48.69, putting Walker 0.28 seconds behind event winner Lisa Buckwitz of Germany, American Kaysha Love was second and German Laura Nolte third.
Fellow QAS pilot Sarah Blizzard finished 23rd.
After four monobob World Cup events this season, Walker is ranked third on the standings, and Blizzard is in 17th.
A two-woman event also took place in Innsbruck, with Walker teaming up with brakewoman Kiara Reddingius, finishing in 11th place. Sarah Blizzard and brakewoman Ashleigh Werner were 21st.
Germany clean swept the two-woman podium with Laura Nolte/Deborah Levi first, Kim Kalicki/Leonie Fiebig second, and Lisa Buckwitz/Neele Schuten third.
After the race Walker commented.
“Always love sliding in Igls, very tight racing and no room for errors which makes for an exciting weekend.”
“Of course I would have loved to finish on the podium in the monobob, but it didn’t quite come together in the last run so had to settle for fourth.
“The two-man didn’t really come together either. Still learning our new sled and trying new things. Sometimes it pays off and sometimes you learn, so we will take the learnings and apply it for the coming races.”
The IBSF tour is returning back to St Moritz, Switzerland, for a second time in as many weeks, with three events taking place on the historic handcut ice Cresta Run. The first monobob race will run on January 24, a second monobob on January 25 and the two-woman on January 26.