Did those really happen as we've been told they did?

I don't know.  Prolly not.

Here, read this:

https://unherd.com/2021/11/there-is-no-spiking-epidemic/

Quote from that link:

"First, let’s talk about needle druggings. There are stories. In the US, for instance, eight people died at a festival, apparently crushed during a crowd surge. There were unrelated reports of a security guard and others being jabbed with a needle. But none of them have been confirmed.

And jabbing someone with a needle is not easy. One academic I spoke to said that “incapacitating someone with a needle is something the NKVD [the Russian secret police] would have to do”. It hurts, for a start; and getting it into the bloodstream via the leg or back is “really inefficient”. The dosing would be amazingly hard to get right, as would doing it without someone noticing for the several seconds it takes to press the plunger on the syringe. The idea that it’s widespread is incredibly unlikely."