"Found not guilty" and "innocent" are not the same thing. "Conviction overturned because of prosecutorial mistakes" and "innocent" aren't even in the same ballpark. Nobody is questioning whether Cosby did it—the evidence at the heart of this is his admission that he did. The issue is whether that evidence could be used in his conviction.

> Cosby is legally innocent

I feel this captures the extent of what you're saying, unless we're making an implicit claim about "using the word innocent in this context has X,Y,Z societal side effects", etc etc

Using the word "innocent" implies that they didn't do what they are accused of.