• I’m not really sure how much more I can elaborate. I haven’t read the book—I read Flemmings book, see below, and found it to reference “Munich, Prologue to Tragedy”, so I went ahead and quoted it. Here is the full footnote which that part came from (with my own inserts in []):

      quote

      On September 11 [1938] M. Bonnet, at Geneva, conferred with M. Litvinov and M. Comnen, the Rumanian Foreign Minister. On this occasion M. Litvinov repeated his assurances that Russia would support France in accordance with the Pact of 1935 and informed him that Rumania had agreed to permit Russian troops to pass through her territory to the assistance of Czechoslovakia as soon as the League of Nations had pronounced Czechoslovakia to be a victim of aggression. He therefore advocated to M. Bonnet the urgent necessity of a joint démarche to the League. M. Bonnet again refused this suggestion and, in reporting the results of his conversation to the French Cabinet on the following day, said that the Russians and Rumanians had “wrapped themselves in League procedure” and had shown little eagerness for action

       

      France didn’t uphold their part of the 1935 Pact, so the Soviet Union never came to help Czechoslovakia under the Pact. And President [of Czechoslovakia] Benes didn’t call upon the Soviet Union “outside” of the Pact:

      The Cold War and Its Origins, Denna Frank Flemming, p. 84

      In justification of the crucifixion of Czechoslovakia at Munich it was said that Russia could not be trusted and that her assistance would not be worth much in any case. On the points there could be honest difference of opinion, but not about the diplomatic record. Certainly the Czech Government did not doubt Russia’s sincerity. At a session of the Harris Institute at the University of Chicago in August 1939 I asked President [of Czechoslovakia] Benes whether Russia would have supported him had he decided to fight in September 1938. He replied, without an instant’s hesitation: “There was never any doubt in my mind that Russia would aid us by all the ways open to her, but I did not dare to fight with Russian aid alone, because I knew that the British and French Governments would make out of my country another Spain.”

       

      The rest of your comment is quite consistent with my own understanding of how things went down, which I got from Flemmings book.