> But the few experts that are able to verify the process and have the computer knowledge

It sounds like you are not familiar with the concept of verifiability or more precisely E2E-V for evoting systems that can be attained. The goal is to never trust the software that is running the machines or officials and thoose are kept accountable with a public cryptographic evidence produced along with final tally. They still are trusted with not sabotaging the process and assuming that one or few parties are not corrupt to ensure vote anonimity, but never with integrity.