https://wizardofodds.com/games/major-multipliers/
Above is a link to a Wizard of Odds website that explains the game.
Random multipliers are assigned (in non-wild games) when dealt a pair of Jacks, Queens, Kings, or Aces that, on the draw, improves to two pair, three of a kind, a full house or any of the various fours of a kind. Dealt two pair hands or dealt trips also produce random multipliers to the categories mentioned so long as there is improvement over the dealt hand. E.g., when dealt two pair, there is no multiplier for ending with two pair; and, likewise, when dealt trips, there are no multipliers produced for a final hand of three of a kind OR two pair.
Certainly, it is true that many of the multipliers granted seem to be irrelevant given a particular dealt hand, and this occurs often in games that offer different payouts for different ranks of four of a kind. This would not be the case for a Jacks or Better game where all fours of a kind pay the same amount. Nevertheless, the addition of these multipliers doesn't really harm anything, so long as players' heads don't explode. Just ignore those you think are extraneous.
CBK, your use of the term "possible hands" may be a bit misleading. Actually, though it may seem far-fetched at first, no matter what cards you are originally dealt, every one of the 2,598,960 hands (in 5 cards per hand, 52 cards per deck games) are still possible on the draw (even though many are quite unlikely with about 59% of these having odds of more than 1.5 million to one against them occurring). Whether dealt a royal flush, various suits of 10 8 6 4 2, or trip aces plus 2 other non-ace, non-rank-matching cards, you can toss 4 cards from the royal flush, all 5 from the garbage hand or, more conventionally toss the two non-ace cards that came with the trip aces in an effort to get 4 aces. A final hand of four aces is clearly possible even if you weren't dealt any aces; and the various multipliers will influence which set of cards is the optimal hold.
Because some of the multipliers in this game are so large, you could have some unconventional plays. When dealt 2 pair like 22KK6 in Double Double Bonus, depending on how the various 4-of-a-kind multipliers are distributed and the values of the full house and 3-of-a-kind multipliers, the optimal play may be holding the two pair, or it could be just holding the two kings, or even holding only the pair of deuces. Yes, for most purposes, the software could have been programmed to ignore the 4 aces with and without kickers multipliers for such a hand, but it doesn't really change anything to have the simpler procedure of generating and showing all multipliers for all qualifying dealt hands.
A couple other things that seem different for this game than for most others again involves those unusually large multipliers. The two-pair multiplier can get up to 100x, which sometimes means that two pair pays more than a full house even with a full-house multiplier. In cases like this, if you end up with a full house, the game will instead pay you the two-pair reward if it is higher than that of the full house.
Also, unlike other games that have more conventional strategies, when two pair has a huge multiplier, with a dealt hand like KK 7 5 2, it may be optimal to hold an additional card along with the pair of kings; it doesn't matter which of the 3 cards is held. Holding three cards cuts down on the probability of a lower paying 3 of a kind and increases the odds of getting that (e.g.) 100x payout for two pair.
All this is a lot to digest, so I certainly wouldn't blame you or anyone if you wanted to pass on this (or other) games that are too complicated. But I was surprised to see that my local casino, which is usually a late adopter, installed this game among their offerings quite soon after Major Multipliers was introduced here at videopoker.com. We'll see how long they stay.
Best of luck regardless of your decision. I hope some of above was what you were looking for.