Log into the Pulumi Console using your GitHub account (the one that doesn’t have access to your SAML organization’s stacks). Then navigate to
https://app.pulumi.com/account/profile.
You will see several “CONNECT” buttons that will allow you to associate other identities with your Pulumi account. If you click the SAML icon, it will prompt you for a SAML based organization, and then login with those SAML creds.
You should then have your SAML identity associated with your Pulumi account, and as a result, access to that organization’s stacks.