The OP article links to unz.com, about which I am unfamiliar, but which appears to promote holocaust denial, conspiracy theories and white supremacy. As such the source of this may be very dubious indeed.
That said, if Floyd did in fact die of an overdose and not because of police actions, then I would have no problem whatsoever with that coming out, were it to be the truth. But at this point consider me pretty sceptical of the source here. Perhaps someone with more familiarity can correct me on that if necessary.
This is what wiki says about unz:
https://en.m.wikipedia.org/wiki/Ron_Unz