Split email delivery using Gsuite and server email

We currently have a Linux server through Media Temple using Plesk. For a single domain, we want to have 2 email addresses that use Gsuite for their email services and 10 email addresses that use the server's email services. We currently have this configured but it's not working correctly and creating issues sending emails back and forth between team members for the domain. Details of what we're trying to do can be found in this article: [login to view URL] We are looking for someone who is experienced working with Linux servers and Gsuite to reconfigure the server to work properly so all emails within the same domain can email back and forth without issues. Note that there are several other domains hosted on this server. This is a project we're looking to complete as soon as possible. Please apply with your skills, rate and when you can have this job completed. Thank you.