I touched on Goudey's use of Ruth and Gehrig in 1933 (both) 34 (Lou) 35 (Babe) via their shared sports agent, Christy Walsh, in an article for SABR.
sabrbaseballcards.blog/2023/05/11/1935-goudey-over-the-border-line/
Walsh handled endorsements for many sports stars and appears to have set up 1934 Goudey as a vehicle for Gehrig that paralleled his Wheaties endorsement and attempt to make Lou a movie star. Chuck Klein was also a client of Walsh, which might be why he appeared for one series that year. (Ruth still appeared in the 1934 World Wide Gum set using his 1933 card photo, so perhaps those deals focused on the USA more than Canada.) Klein's also missing from Diamond Stars, so perhaps Walsh asked for higher prices on all three than National Chicle cared to pay.
Big fan of the proof sheet of proposed DS cards that surfaced after bankruptcy and wish the company had survived long enough to print them.