I'm the creator of https://opt-out.eu and I can confirm that you are correct. It works, in the vast majority of cases.
The last company I made erase me was cdon.com after I bought something on sale there and they demanded my SSN to pay with credit cards. I see that they are missing from your site, their DPO email is: dpo@cdon.com
I also like "This service does not collect or trade any personal data."