NOTICE - TRY AT OWN RISK - To make extra voices installed on your PC available to Cartoon Animator 5 you can use the method mentioned here: https://www.ghacks.net/2018/08/11/unlock-all-windows-10-tts-voices-system-wide-to-get-more-of-them/
Further to my last, I believe it also requires a registry tweak to enable the facility to choose all voices, but it would be great if we could do this from within the program.
I believe these are dependent on what voices you have installed in Windows. You can also add custom ones in Windows. Google will let you know how. I only have Hazel and Zira at the moment, but before upgrading my PC I'd managed to install all the Microsoft ones, but you can also add third party ones. You could try this as a starting point: https://support.microsoft.com/en-us/windows/appendix-a-supported-languages-and-voices-4486e345-7730-53da-fcfe-55cc64300f01