Fran, this is a complex thing, I believe. I will have to do a little "reasonable speculating" to make my [tentative] views clear--but here they are:
1). Ruppelt gives 3 cases that he says Dewey used. At least 1, and maybe all 3, of those cases do not harmonize well with Dewey's Robertson Panel "handout". I believe nevertheless that both Ruppelt and the handout are "true". This is because one can make an argument for UFOs showing intelligence in their "motions" by noting two kinds of motion characteristics [a). formation flying, and b) behavior indicating "intent" of some kind--ex. approach; evade; circle; stalk or pace; etc]. Ruppelt's cases are more the "behavior-of-intent" sort, while the handout is obviously the artificial display of "formation". Therefore, I believe that we start fresh with Dewey's handout and see where we go. BTW, I believe that the USN analysis of the Tremonton film was an entirely separate "third leg"of his argument, that he knew would be taken care of by Woo and Neasham at the Panel without any effort on his part.
2). I have noted that the first case diagrammed by Dewey must be the May 1,1952 George AFB [CA] case. Also, the sixth case must be the July 14, 1952 Chesapeake Bay [Nash-Fortenberry] case. The eleventh case seems almost surely to be the July 24,1952 Carson Sink [NV] case. I'd bet pretty strongly on the fourteenth being August 3, 1952 Truth or Consequences [NM] case. If one makes a list with blanks to be filled in on it, then one notices that those four cases are in date order. So, a second "working hypothesis"/wild-stupid-guess: Might Dewey not have put the whole list in date order? Also, this would place the cases that he used within his own tenure on the UFO desk, thereby adding a bit more "confidence" [?] "convenience" [?] to his mind. Also it would place them in the period that persons like Stefan Possony and Colonel Bill Adams [who different sources say influenced him] would have been actively on scene.
3). Operating on that lightly-baked hypothesis, case 2 could be May 13 [18?], 1952 Greenville [SC] , and case 3 June 8, 1952 Albuquerque [NM]. This
latter is almost certainly one of those two. Case 17 might be August 24, 1952 Hermanas/El Paso [TX], which if true "bookends" the study dates.4). Now for completely unbaked throwaways: candidates for 16 are probably several--August 19, 1952 Red Bluff [CA] or August 22, 1952 Ontario [CA] are two. Could July 20, 1952 Lavalette [NJ] be #9? Could July 21, 1952 Weisbaden [GER] be #10? Could some interpretation of July 28, 1952 Kirtland AFB [NM] be 13? My suggestions get weaker and weaker in my mind as these go.
5). This hypothesis or listing pattern will probably be easy for someone to support or overthrow or even simply massage. This is because most of the very dramatic diagrams [#4,7,8,13, &15] have no seriously "identified" candidate. Someone will locate the cases with 6-7-8-10 UFOs and firmly fix dates for some of them. OR, if no such cases are ever found, given a good try, then Dewey must have been in part working from UFO case reports that aren't in Blue Book. That would be quite interesting as well.6). I note that "holes" in my pattern occur at #s 7 & 8 and ~13. If the date scheme is correct, then these could be interpreted as around the times of the two Washington DC events. Dewey played a role in these and may have been working off some sort of reports that gave some "formation-flying" elements to either or both of these cases.
7). If any of this makes sense, Fournet would have gone to the Robertson Panel with at least a tripled-barreled argument for intelligence behind the UFOs: a) Formation-flying, which is so "geometrical" that it is in itself "intentional" and thereby a sign of intelligence; b) "intentional behavior" cases involving single UFOs, the actions of which, nevertheless, demonstrate intelligent action on the part of the controllers; c) the Tremonton film analysis, which is the "granddaddy" case of formation-flying and [being film] close to being physical proof. The issue of whether this demonstrated "extraterrestriality" or not would rise or fall on whether one believed the US or USSR could make anything like that. Note, also, that the whole attitude of Fournet, Woo, Neasham, Adams, and probably Possony, Garland, Weldon Smith, etc is that there's no doubt that these things are real--they've moved on from that.