>>pests+(OP)
I think the optics of this aren't great. You ask someone to copy their voice, they say no and then (maybe coincidentally) you release a voice designed to sound very similar. Legally this may well be fine but come on, didn't anyone think this might make them look bad?
>>Dharma+U4
Sure, but to me it looks bad from the other perspective too if this is made into a problem. A person's natural voice is their voice and some celebrity should NOT be able to dictate how it is used.
>>pests+(OP)
The VA has not been identified, but I bet that she has a showreel in which you can hear at least ten different natural voices that are not at all like SJ's performance in 'her'. A sad read for the local undertaker. A maniacal shouty ad for the monster truck rally. A motherly read for baby formula. Some fun accents. A dramatic read.