I did not know of this sign, did not know that it existed, so how does a man on a roller coaster know when to use it and why would these three men be in the know? Welch is not flashing a sign as he is holding the camera w/both hands.
The upper-right pic with the Baphomet (horns) hand sign also features the following sign on the hand in right side of pic:

MANO PANTEA
In Rome this little hand is well known, and is called by everybody the Mano Pantea.
The use of hand gestures giving blessing is an ancient motif in art. This particular gesture of the fingers is known as the mano pantea, which predates Christianity and can be seen in Pagan motifs to ward off evil eye, and Ancient Egyptian artifacts invoking parental protection.

The frog, it may be noted, in both cases seems to have its proper position, and that well known, aphrodisiac, was surely placed by design in close relation to the middle finger, the ancient digitus infamis. I find the frog to be curious considering the display of frogs on Merovingian crests and coat of arms motifs.
Upon the Mano Pantea we may safely consider it under either, or all of the four first meanings; and hence as it was in Egypt a powerful amulet to guard both living and dead, so we may well believe it was adopted as such by the Romans along with the Serapis cult. It will be noticed that our jeweler’s description passes over the scarab, which is nevertheless very distinct on the original bronze.
On the back of the hand we have the frog, which our friend calls a toad (rospo). This is a common amulet against the evil eye. In Naples the simple frog amulet is called a Sirena, like the more elaborate one of which a description follows later. It is not only now worn by Italians, Greeks, and even Turks, but it appears on many ancient gems and medals. It is commonly of metal, but when cut out of amber or coral is of greater power. The frog also was among Egyptians “a symbol of Ptah,” because, as Horapollo says, “it was the representation of man in embryo, that is, of the being who, like the world, was the work of the Creative Power, and the noblest production of his hands.”
“The importance attached to the frog in some parts of Egypt is shown by its having been embalmed, and honoured with sculpture in the tombs of Thebes. The frog was the symbol of hefnu, 100,000, or an immense number. It sat on a ring or seal, a sign occasionally used in lieu of the Tau or ‘life.'” Again we are told, “la grenouille rappelait l’idée de la renaissance.” is from Maspero’s Archéologie, p. 235. Jahn gives a plate (Taf. IV.) of a terra-cotta lamp, now in the Berlin Museum, having an eye for centre, round which are the frog, scorpion, phallus, snail, and two monkeys’ heads (cynocephalus); the spout is formed of a horned mask. The frog is shown on the Kertch necklace (p. 135) as one of the special amulets. There is also an ancient bronze frog amulet, prepared for suspension, in the Ashmolean Museum.
Pliny says: “To this the Magi add some other particulars, which, if there is any truth in them, would lead us to believe that frogs ought to be considered much more useful to society than laws.” He gives directions for a particular manipulation of the frog, by which a wife conceives an aversion to all paramours. One kind (phrini), known to the Greeks, have protuberances like horns. He also says, there is a small bone on each side of a frog. That on the right side has many wonderful properties one is, that if thrown into boiling water it will immediately cool, and that it will not boil again till the bone be removed. The little bone from the left side, on the other hand, has the property of making it boil. It will also assuage the fury of dogs, and if put into drink it will conciliate love and end discord or strife. It is also worn for a talisman as an aphrodisiac.
One of the two frog charms on is that common in Rome, while the clumsier one is Neapolitan. The two shown immediately beneath the Mano Pantea on the same plate are from Constantinople, sold openly as charms in the bazaars. Evidently the frog as an amulet is widely used among various races, ancient and modern.

https://mysteryoftheiniquity.com/201...igns-gestures/