Thanks for reaching out to Microsoft Q&A.
The requirement to "add a team member" for progressing to Level 4 in the Microsoft for Startups Founders Hub program is indeed mandatory. This is part of the criteria for receiving up to $150,000 in Azure credits. The intent is to demonstrate the growth of your startup by adding someone who actively contributes to the business.
That said, the program does not specify that the team member must be an employee, but they should have a LinkedIn profile and accept the invitation through the Founders Hub platform. While it might technically be possible to add a friend or relative, it's advisable to ensure that the person plays some role in the startup, even if it's an informal one, to align with the spirit of the requirement.
For more details or to verify your specific case, you can always contact support through the Founders Hub portal (https://learn.microsoft.com/en-us/microsoft-for-startups/benefits/get-more-benefits). You can explore more here: Founders Hub Portal
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