Hello, I am ready to help you in changing DNS setting back. I need to know your domain name, the domain name (CNAME) or IP of your dedicated mail server and have an access to domain management panel or NS server. You only need to change MX records back. It is an easy task and i can start right now. You may pay only after all job is done. Will do my best. Thanks in advance, Stan
PS : I also propose to temporary keep Google MX records but decrease priority. If everything is fine, the emails go to your mail server (higher priority) but in case of any troubles, the emails will go to Google. It will help to avoid an impact. When you validate that all is fine, i'll delete Google MX records completely.