Dataveria opt-out help

I've been trying to get my data removed from various data brokers following Yael's guide on github. When I followed Yael's recommended method, the website form didn't work, so I emailed their support directly with a proton mail account so I didn't provide any new information.

After some back and forth, I got his response:

Hello,

We apologize, but we only accept requests made from public email addresses (Gmail, Yahoo, etc).

People Report Support Power your business with the most accurate data and public records from across the country.

What are "public email addresses"?

Is it just some made-up term they use to discourage me so I give up?

Should I just keep emailing them?

Thank for any advice