Er, that is totally possible? You act like it's not a machine learning system. You train new stuff in hours or days easily, especially if you have good tooling. Imagine saying this of, say, Stable Diffusion image LoRAs: "this X artist LoRA couldn't be based on X because it was somehow trained within the few weeks after X said no!"
All the timing means is that, in good management & startup fashion, because they needed multiple voices, they had a voice pipeline going, and so could have a bunch of female voices in the pipeline for optionality. And if licensing Johansson didn't work out, you have a plan B (and C, and preferably D). This is big business, you don't do things serially or not have backups: "'hope' is not a plan".