I suppose so, but I believe they always make sure not a single trace of Earth life is left on the equipement they sent to Mars, for obvious reasons. So they already control for that.
Besides looking pretty messy, I'm not sure this does any harm.
I'm glad the article mentions that in this case, it really doesn't matter; like, there seems to be nothing to 'pollute' on Mars (also 7 tonnes is not much at all). Bit of a strange headline to me.
I feel like the solution is pretty simple: if you want to AI copy someone's voice and put it in your project, you have to hire them and pay them as normal, and they have to give consent to let the AI use their likeness.