It is reasonably common in the voicing part of the acting industry, when a famous name turns you down, that you instead turn to a voice imitator to give a performance that's reminiscent of a number of factors (kind of sounding like this other person, for example).

This way, legally you're in the clear, because you didn't use the voice of X. Not on any occasion did you use the voice of X. You even paid a voicer to make your recordings, and it's their voice.

Morally, it can be - and probably is - a different matter.