To prevent external, inbound messages from known senders from being incorrectly classified as spam, add the sender's domain to an allowlist in the Admin console.
Access Gmail Settings in Admin Console:
Go to the Google Admin console.
Navigate to Apps > Google Workspace > Gmail > Spam, Phishing, and Malware.
Add Approved Senders:
In the Spam settings, find the section for "Email whitelist" or "Approved senders".
Click on "Configure" to add a new entry.
Specify the Sender's Domain:
Enter the domain of the external sender that needs to be allowed.
Save the changes to update the whitelist.
Verify and Monitor:
Ensure that the settings are applied and monitor the spam filter to confirm that the known sender's emails are no longer being flagged as spam.
By adding the sender's domain to an allowlist, you instruct the spam filter to accept emails from this domain, reducing false positives.
Reference:
Prevent mail from being marked as spam
Approved sender list in Gmail

To troubleshoot video degradation issues in Google Meet, the first step should be to locate the Meet Quality Tool and review the output for issues with quality. This tool provides detailed insights into the performance and quality of Meet calls, including network metrics, device performance, and user feedback. By analyzing this data, administrators can identify specific causes of degradation and take appropriate actions to resolve them.
References:
* Google Workspace Admin Help - Use the Google Meet quality tool

Reference: https://support.google.com/chrome/a/answer/4600997?hl=en

https://support.google.com/a/answer/9275380#licenses:~:text=Context%2DAware%20Access-,Control%20access%20to%20apps%20based%20on%20user%20%26%20device%20context,context%2C%20such%20as%20whether%20their%20device%20complies%20with%20your%20IT%20policy.,-Context%2DAware%20Access
https://support.google.com/a/answer/9275380?hl=en&fl=1
https://support.google.com/a/answer/9007320?hl=en&fl=1

* Secondary Domain:
* A secondary domain allows you to add another domain to your existing Google Workspace account without creating a separate account.
* This is useful for managing users from different domains under a single Google Workspace instance.
* Steps to Add a Secondary Domain:
* Navigate to the Google Admin console.
* Go to Account > Domains > Manage domains.
* Click "Add a domain" and select "Add another domain".
* Enter the domain name (mystartup.com) and follow the prompts to verify domain ownership by updating DNS records.
* Once verified, create users under the secondary domain:
* Navigate to Directory > Users.
* Click "Add new user" and enter user information, selecting the secondary domain for their email address.
* Ensure all existing security policies are applied by assigning the users to the appropriate organizational units.
References
* Google Workspace Admin Help: Add a Domain