I guess if I had to say a reason I just don't believe you can create a solution this quick unless you created the virus. Like a computer expert could create a virus and sell the anti virus software to.make that much more.
I guess there could be a possibility that Pfizer, Moderna, AstraZeneca, and J&J all were involved in a secret conspiracy together and released the virus they invented in Wuhan, blamed China for it, then introduced 4 different vaccines to raise their stock share prices.
Or it could be aliens from another star system. However I tend to go with the Occam's Razor rule first
