Spitballing…
What if the vaccines actually work, but all the clots, illnesses, and other B.S. are coming from somewhere else, being mixed up in the data. Essentially, hiding a genocide, or better said, a targeted killing within a generalized culling within a vaccine rollout. In this scenario, perhaps the vaccine is wildly effective AND CHEAP, and (((they))) fucking hate that. They're losing, so they are killing off their minions and taking some other innocents with them and trying to muddy the waters around what could be a good technology.
Then again, a mind fuck this tangled would require this evil people to be smart.