Based on comments made by Russ Davis during the match, I'm going to guess that the Thesz-Gagne match from the Chicago footage is from 1/25/52. Not 100% sure. Wrestlingdata is far from being complete of course, but they list two Chicago Thesz-Gagne matches from the time period, both Broadways - 1/25/52 and 12/12/52. Davis on commentary implies this is the first time they have wrestled in Chicago, so that would suggest the former. Again, just a guess.
Great match BTW