When you do not have the Global Admin credentials for a customer, the system provides a way for you to send an authorization link to the customer, which allows the customer to authorize the partner to manage the customer tenant.

1. Click Authorization link, and the Authorization link panel appears.
2. Enter the email address of the customer’s Tenant Owner account.
3. Click Generate authorization link. The generated link will be displayed in the textbox. The link is only valid within 72 hours.
4. Click Copy to copy the link. Then, you can send the link to the customer you want to invite. After the customer clicks the link and completes the authorization, you can manage the customer in Elements for Partners.

Guide can be found here: Invite a New Customer

Make sure you Procure the Licenses to the same user that setup the Account with GA!