Do you have a time frame for completion on this job? I like to allocate about 2 days for storyboarding, and then 3 - 5 days to animate per minute. So the maximum amount of time I will need for the 4 videos, will be about 30 days. If graphics are reused, it will shorten the time it takes. I have done a few similar to this, except in the medical and veterinarian field. I can provide samples of voice over artists, that match your neutral american, or Australian request, which you can choose from. It's no problem to hand over the after effects files and MP3 voice overs, and graphics once completed.
If you wish to discuss further, I am available to chat, just let me know the best time that suits you, and which platform you prefer.
Many thanks
Debbie