I need time. I cant answer quickly. But, I think it's good to know what relationship Constantia and Camilla With Castor and Pollux. They are the passive agents. Castor and Pollux receive the emblems, the gifts of the gods and give them to the bride and groom. "The wedding was held in May? Gemini: May 22-June 21
Yes, this is one argument.
We have the first note of a game called Minchiate in 1466 in a letter of Luigi Pulci to Lorenzo Medici. 1471 and 1477 the game is mentioned again, in 1477 it is "allowed". We cannot be sure, that this game was similar to the game with the name Germini, which later appears in Florence in 16th century. In ca. 1552 a game exists, which has 40 trumps and probably a similar game structure as the deck version of 1725, which is complete and known ... and as we know it.
The later Minchiate had 40 trumps and these were arranged in the manner, that cards 1-15 + 5 unnumbered cards builded one half (similar to usual Trionfi or Tarot cards) and the 20 other consisted of the cards 16-35 and presented 3 theological virtues + Prudentia, 4 natural elements and 12 zodiac signs. The whole coulb be described as a 2x20-structure.
"Germini" is taken from "Gemini", as the card of Gemini is the highest numbered trump (Nr. 35). Germini is also taken from a game Gherminella in 14th century Florence, which was played with a stick and two cords, and used to play humble betting games for money. The two cords were "twins". Geminella was used for a specific type of pasta, which looked a little bit like two Gherminella cords.
In the 5x14-theory, which assumes, that early Trionfi decks had mainly 5x14 (14 special cards) or arrangements with 16 special cards, the development is assumed, that 6 additional cards were developed for the 5x14-deck during the Ippolita marriage in May 1465. Then - hypothetical - a deck existed with 4x14 + 20 cards ... the socalled Pierpont-Morgan-Bergamo-deck.
In a part of the background of this activity the young Lorenzo de Medici from Florence participated (hypothetically). The circle of youth around Lorenzo + the elder poet Luigi Pulci are expected to have experimented with different Trionfi cards and sets - at least this is a plausible idea, as Lorenzo and Pulci exchanged about the Minchiate game.
The highest card in this deck was the World card, showing two putti, interpretable as "twins".
Possibly it's the first deck, which arranged it's permanent trumps higher than 16. So the idea with twins or "Gemini" cards might be already playing card custom in 1475.
In Chess we had with the Cessolis interpretation, that the pawns were specialized to individual professions according the chess officers behind, for instance the queen pawn was physician, as women need physician, and the knights had a smith and a doorkeeper, as knights need smiths for their weapons and doorkeepers to give alarm in cases, when the city is attacked.
So the pawns became twins to the chess officers, similar as we find 12 gods with messenger in the wedding book of 1475.
Cessolis' idea was from ca. 1300, so "very old".
Generally playing card sets can be interpreted as twin structure, as 2 suits usually did run from 1-10 and 2
did run from 10-1. The expression "paro" (pair) was used to signify "one deck" already in 14th century.
And so we have Castor and Pollux in a special function in the wedding book 1475, operating on the base of a broad tradition ... .-)